diff --git a/backend/internal/handler/grok_media.go b/backend/internal/handler/grok_media.go
index f51167c6e6..77c3e74abc 100644
--- a/backend/internal/handler/grok_media.go
+++ b/backend/internal/handler/grok_media.go
@@ -164,8 +164,17 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 		sessionSeed = []byte(requestID)
 	}
 	sessionHash := h.gatewayService.GenerateExplicitSessionHash(c, sessionSeed)
+	boundLookupAccountID := int64(0)
 	if endpoint.IsVideoLookupRequest() {
-		sessionHash = service.GrokMediaVideoRequestSessionHash(requestID)
+		sessionHash = service.GrokMediaVideoRequestSessionHash(requestID, subject.UserID, apiKey.ID)
+		boundLookupAccountID, err = h.gatewayService.ResolveGrokMediaVideoRequestAccount(
+			c.Request.Context(), apiKey.GroupID, requestID, subject.UserID, apiKey.ID,
+		)
+		if err != nil || boundLookupAccountID <= 0 {
+			reqLog.Info("grok_media.video_lookup_owner_binding_missing", zap.Error(err))
+			h.errorResponse(c, http.StatusNotFound, "not_found_error", "Video request not found")
+			return
+		}
 	}
 	requestCtx := c.Request.Context()
 	failedAccountIDs := make(map[int64]struct{})
@@ -240,6 +249,14 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 			h.errorResponse(c, cls.Status, cls.ErrType, cls.Message)
 			return
 		}
+		if boundLookupAccountID > 0 && selection.Account.ID != boundLookupAccountID {
+			reqLog.Warn("grok_media.video_lookup_bound_account_unavailable",
+				zap.Int64("bound_account_id", boundLookupAccountID),
+				zap.Int64("selected_account_id", selection.Account.ID),
+			)
+			h.errorResponse(c, http.StatusNotFound, "not_found_error", "Video request not found")
+			return
+		}
 
 		reqLog.Debug("grok_media.account_schedule_decision",
 			zap.String("layer", scheduleDecision.Layer),
@@ -300,6 +317,10 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 					h.handleFailoverExhausted(c, failoverErr, false)
 					return
 				}
+				if endpoint.IsVideoLookupRequest() {
+					h.handleFailoverExhausted(c, failoverErr, false)
+					return
+				}
 				if failoverErr.RetryableOnSameAccount {
 					retryLimit := account.GetPoolModeRetryCount()
 					if sameAccountRetryCount[account.ID] < retryLimit {
@@ -351,7 +372,9 @@ func (h *OpenAIGatewayHandler) handleGrokMedia(c *gin.Context, endpoint service.
 
 		h.gatewayService.ReportOpenAIAccountScheduleResult(account.ID, account.GetMappedModel(requestModel), true, nil)
 		if endpoint.IsGenerationRequest() && strings.TrimSpace(result.ResponseID) != "" {
-			if err := h.gatewayService.BindGrokMediaVideoRequestAccount(requestCtx, apiKey.GroupID, result.ResponseID, account.ID); err != nil {
+			if err := h.gatewayService.BindGrokMediaVideoRequestAccount(
+				requestCtx, apiKey.GroupID, result.ResponseID, subject.UserID, apiKey.ID, account.ID,
+			); err != nil {
 				reqLog.Warn("grok_media.bind_video_request_account_failed",
 					zap.Int64("account_id", account.ID),
 					zap.String("request_id", result.ResponseID),
diff --git a/backend/internal/service/grok_media.go b/backend/internal/service/grok_media.go
index a107bd72f3..36bd80f728 100644
--- a/backend/internal/service/grok_media.go
+++ b/backend/internal/service/grok_media.go
@@ -269,16 +269,50 @@ func parseGrokMediaMultipartRequest(contentType string, body []byte, info *GrokM
 	}
 }
 
-func GrokMediaVideoRequestSessionHash(requestID string) string {
+func GrokMediaVideoRequestSessionHash(requestID string, userID, apiKeyID int64) string {
 	requestID = strings.TrimSpace(requestID)
-	if requestID == "" {
+	if requestID == "" || userID <= 0 || apiKeyID <= 0 {
 		return ""
 	}
-	return "grok-video:" + DeriveSessionHashFromSeed(requestID)
+	ownerSeed := fmt.Sprintf("%d:%d:%s", userID, apiKeyID, requestID)
+	return "grok-video:" + DeriveSessionHashFromSeed(ownerSeed)
 }
 
-func (s *OpenAIGatewayService) BindGrokMediaVideoRequestAccount(ctx context.Context, groupID *int64, requestID string, accountID int64) error {
-	return s.BindStickySession(ctx, groupID, GrokMediaVideoRequestSessionHash(requestID), accountID)
+func (s *OpenAIGatewayService) BindGrokMediaVideoRequestAccount(
+	ctx context.Context,
+	groupID *int64,
+	requestID string,
+	userID, apiKeyID, accountID int64,
+) error {
+	if s == nil || s.cache == nil {
+		return fmt.Errorf("grok video request binding cache is unavailable")
+	}
+	sessionHash := GrokMediaVideoRequestSessionHash(requestID, userID, apiKeyID)
+	cacheKey := s.openAISessionCacheKey(sessionHash)
+	if cacheKey == "" || accountID <= 0 {
+		return fmt.Errorf("grok video request binding is invalid")
+	}
+	ttl := openaiStickySessionTTL
+	if s.cfg != nil && s.cfg.Gateway.OpenAIWS.StickySessionTTLSeconds > 0 {
+		ttl = time.Duration(s.cfg.Gateway.OpenAIWS.StickySessionTTLSeconds) * time.Second
+	}
+	return s.cache.SetSessionAccountID(ctx, derefGroupID(groupID), cacheKey, accountID, ttl)
+}
+
+func (s *OpenAIGatewayService) ResolveGrokMediaVideoRequestAccount(
+	ctx context.Context,
+	groupID *int64,
+	requestID string,
+	userID, apiKeyID int64,
+) (int64, error) {
+	if s == nil || s.cache == nil {
+		return 0, fmt.Errorf("grok video request binding cache is unavailable")
+	}
+	cacheKey := s.openAISessionCacheKey(GrokMediaVideoRequestSessionHash(requestID, userID, apiKeyID))
+	if cacheKey == "" {
+		return 0, fmt.Errorf("grok video request binding is invalid")
+	}
+	return s.cache.GetSessionAccountID(ctx, derefGroupID(groupID), cacheKey)
 }
 
 func (s *OpenAIGatewayService) ForwardGrokMedia(
@@ -369,7 +403,8 @@ func (s *OpenAIGatewayService) ForwardGrokMedia(
 
 	requestIDHeader := firstNonEmpty(resp.Header.Get("x-request-id"), resp.Header.Get("xai-request-id"))
 	requestModel := requestInfo.Model
-	if resp.StatusCode >= 400 {
+	preserveContentRangeError := endpoint == GrokMediaEndpointVideoContent && resp.StatusCode == http.StatusRequestedRangeNotSatisfiable
+	if resp.StatusCode >= 400 && !preserveContentRangeError {
 		return s.handleGrokMediaErrorResponse(ctx, resp, c, account, requestIDHeader, requestModel)
 	}
 
@@ -859,7 +894,7 @@ func isGrokMediaVideoContentURL(rawURL, requestID string) bool {
 	if err != nil || parsed.Path == "" {
 		return false
 	}
-	segments := strings.Split(strings.Trim(parsed.Path, "/"), "/")
+	segments := strings.Split(strings.Trim(parsed.EscapedPath(), "/"), "/")
 	if len(segments) < 3 {
 		return false
 	}
diff --git a/backend/internal/service/grok_media_content_test.go b/backend/internal/service/grok_media_content_test.go
index 7e52b7e2f0..839bc01b68 100644
--- a/backend/internal/service/grok_media_content_test.go
+++ b/backend/internal/service/grok_media_content_test.go
@@ -93,6 +93,67 @@ func TestForwardGrokMediaContentUsesUpstreamCredentialAndStreamsRange(t *testing
 	require.Equal(t, "bytes 0-12/100", recorder.Header().Get("Content-Range"))
 	require.Equal(t, "bytes", recorder.Header().Get("Accept-Ranges"))
 	require.Equal(t, `attachment; filename="task-1.mp4"`, recorder.Header().Get("Content-Disposition"))
+	require.True(t, IsResponseCommitted(c))
+}
+
+func TestForwardGrokMediaContentStreamsFullResponseWithSafeDefaults(t *testing.T) {
+	upstream := &grokMediaContentUpstreamStub{
+		response: &http.Response{
+			StatusCode:    http.StatusOK,
+			Header:        http.Header{"Set-Cookie": []string{"secret=upstream"}, "X-Upstream-Secret": []string{"hidden"}},
+			Body:          io.NopCloser(strings.NewReader("full-video")),
+			ContentLength: -1,
+		},
+	}
+	svc := &OpenAIGatewayService{cfg: &config.Config{}, httpUpstream: upstream}
+	c, recorder := grokMediaContentTestContext(http.MethodGet, "https://api.example/v1/videos/task-1/content", nil)
+
+	_, err := svc.ForwardGrokMedia(
+		context.Background(), c, grokMediaContentTestAccount(),
+		GrokMediaEndpointVideoContent, "task-1", nil, "",
+	)
+
+	require.NoError(t, err)
+	require.Equal(t, http.StatusOK, recorder.Code)
+	require.Equal(t, "full-video", recorder.Body.String())
+	require.Empty(t, upstream.request.Header.Get("Range"))
+	require.Equal(t, "application/octet-stream", recorder.Header().Get("Content-Type"))
+	require.Empty(t, recorder.Header().Get("Content-Length"))
+	require.Empty(t, recorder.Header().Get("Set-Cookie"))
+	require.Empty(t, recorder.Header().Get("X-Upstream-Secret"))
+	require.True(t, IsResponseCommitted(c))
+}
+
+func TestForwardGrokMediaContentPreservesRangeNotSatisfiable(t *testing.T) {
+	upstream := &grokMediaContentUpstreamStub{
+		response: &http.Response{
+			StatusCode: http.StatusRequestedRangeNotSatisfiable,
+			Header: http.Header{
+				"Content-Type":   []string{"text/plain"},
+				"Content-Length": []string{"11"},
+				"Content-Range":  []string{"bytes */100"},
+				"Accept-Ranges":  []string{"bytes"},
+			},
+			Body: io.NopCloser(strings.NewReader("bad-range!!")),
+		},
+	}
+	svc := &OpenAIGatewayService{cfg: &config.Config{}, httpUpstream: upstream}
+	c, recorder := grokMediaContentTestContext(http.MethodGet, "https://api.example/v1/videos/task-1/content", map[string]string{
+		"Range": "bytes=500-600",
+	})
+
+	_, err := svc.ForwardGrokMedia(
+		context.Background(), c, grokMediaContentTestAccount(),
+		GrokMediaEndpointVideoContent, "task-1", nil, "",
+	)
+
+	require.NoError(t, err)
+	require.Equal(t, http.StatusRequestedRangeNotSatisfiable, recorder.Code)
+	require.Equal(t, "bad-range!!", recorder.Body.String())
+	require.Equal(t, "bytes=500-600", upstream.request.Header.Get("Range"))
+	require.Equal(t, "bytes */100", recorder.Header().Get("Content-Range"))
+	require.Equal(t, "bytes", recorder.Header().Get("Accept-Ranges"))
+	require.True(t, IsResponseCommitted(c))
 }
 
 func TestForwardGrokVideoStatusRewritesOnlyProtectedContentURL(t *testing.T) {
@@ -123,3 +184,12 @@ func TestForwardGrokVideoStatusRewritesOnlyProtectedContentURL(t *testing.T) {
 	require.Equal(t, "9007199254740993", gjson.Get(recorder.Body.String(), "counter").String())
 	require.NotContains(t, recorder.Body.String(), "malicious.invalid")
 }
+
+func TestRewriteGrokMediaVideoContentURLsPreservesOtherIDsAndHandlesNestedEscapedID(t *testing.T) {
+	body := []byte(`{"nested":[{"url":"https://relay.example/v1/videos/task%2Fone/content"},{"url":"https://relay.example/v1/videos/task-two/content"}]}`)
+
+	rewritten := rewriteGrokMediaVideoContentURLs(body, "task/one", "/v1/videos/task%2Fone/content")
+
+	require.Equal(t, "/v1/videos/task%2Fone/content", gjson.GetBytes(rewritten, "nested.0.url").String())
+	require.Equal(t, "https://relay.example/v1/videos/task-two/content", gjson.GetBytes(rewritten, "nested.1.url").String())
+}
diff --git a/backend/internal/service/openai_gateway_grok_test.go b/backend/internal/service/openai_gateway_grok_test.go
index 67ad712147..6ed35d4112 100644
--- a/backend/internal/service/openai_gateway_grok_test.go
+++ b/backend/internal/service/openai_gateway_grok_test.go
@@ -878,19 +878,34 @@ func TestForwardGrokMediaVideoMutationEndpoints(t *testing.T) {
 	}
 }
 
-func TestBindGrokMediaVideoRequestAccountUsesRequestIDStickyHash(t *testing.T) {
-	ctx := context.Background()
+func TestGrokMediaVideoRequestBindingIsScopedToUserAndAPIKey(t *testing.T) {
+	gin.SetMode(gin.TestMode)
+	c, _ := gin.CreateTestContext(httptest.NewRecorder())
+	c.Request = httptest.NewRequest(http.MethodGet, "/v1/videos/video-request-123", nil)
+	c.Request.Header.Set("session_id", "shared-client-session")
 	groupID := int64(7)
 	cache := &stubGatewayCache{}
 	svc := &OpenAIGatewayService{cache: cache}
+	const userID int64 = 41
+	const apiKeyID int64 = 51
+	require.NotEmpty(t, svc.GenerateExplicitSessionHash(c, nil))
+	ctx := c.Request.Context()
 
-	hash := GrokMediaVideoRequestSessionHash("video-request-123")
+	hash := GrokMediaVideoRequestSessionHash("video-request-123", userID, apiKeyID)
 	require.NotEmpty(t, hash)
-	require.NoError(t, svc.BindGrokMediaVideoRequestAccount(ctx, &groupID, "video-request-123", 63))
+	require.NoError(t, svc.BindGrokMediaVideoRequestAccount(ctx, &groupID, "video-request-123", userID, apiKeyID, 63))
 
-	accountID, err := svc.getStickySessionAccountID(ctx, &groupID, hash)
+	accountID, err := svc.ResolveGrokMediaVideoRequestAccount(ctx, &groupID, "video-request-123", userID, apiKeyID)
 	require.NoError(t, err)
 	require.Equal(t, int64(63), accountID)
+
+	accountID, err = svc.ResolveGrokMediaVideoRequestAccount(ctx, &groupID, "video-request-123", userID+1, apiKeyID)
+	require.Error(t, err)
+	require.Zero(t, accountID)
+
+	accountID, err = svc.ResolveGrokMediaVideoRequestAccount(ctx, &groupID, "video-request-123", userID, apiKeyID+1)
+	require.Error(t, err)
+	require.Zero(t, accountID)
 }
 
 func TestForwardGrokMedia429ReconcilesRateLimitBeforeCustomErrorBypass(t *testing.T) {