diff --git a/.buildkite/pipeline.yml b/.buildkite/pipeline.yml
index 7375dd4a2..8f942b041 100644
--- a/.buildkite/pipeline.yml
+++ b/.buildkite/pipeline.yml
@@ -29,7 +29,6 @@ steps:
     depends_on: image-build
     commands:
       - pytest -s -v tests/e2e/offline_inference/test_t2i_model.py
-      - pytest -s -v tests/e2e/offline_inference/test_ovis_image.py
     agents:
       queue: "gpu_1_queue" # g6.4xlarge instance on AWS, has 1 L4 GPU
     plugins:
@@ -93,11 +92,28 @@ steps:
           volumes:
             - "/fsx/hf_cache:/fsx/hf_cache"
 
-  - label: "Diffusion Parallelism Test"
-    timeout_in_minutes: 25
+  - label: "Diffusion Sequence Parallelism Test"
+    timeout_in_minutes: 20
     depends_on: image-build
     commands:
       - pytest -s -v tests/e2e/offline_inference/test_sequence_parallel.py
+    agents:
+      queue: "gpu_4_queue" # g6.12xlarge instance on AWS, has 4 L4 GPU
+    plugins:
+      - docker#v5.2.0:
+          image: public.ecr.aws/q9t5s3a7/vllm-ci-test-repo:$BUILDKITE_COMMIT
+          always-pull: true
+          propagate-environment: true
+          shm-size: "8gb"
+          environment:
+            - "HF_HOME=/fsx/hf_cache"
+          volumes:
+            - "/fsx/hf_cache:/fsx/hf_cache"
+
+  - label: "Diffusion Tensor Parallelism Test"
+    timeout_in_minutes: 20
+    depends_on: image-build
+    commands:
       - pytest -s -v tests/e2e/offline_inference/test_zimage_tensor_parallel.py
     agents:
       queue: "gpu_4_queue" # g6.12xlarge instance on AWS, has 4 L4 GPU
diff --git a/tests/e2e/offline_inference/test_diffusion_cpu_offload.py b/tests/e2e/offline_inference/test_diffusion_cpu_offload.py
index cefda8915..cd22b34e0 100644
--- a/tests/e2e/offline_inference/test_diffusion_cpu_offload.py
+++ b/tests/e2e/offline_inference/test_diffusion_cpu_offload.py
@@ -38,8 +38,10 @@ def test_cpu_offload_diffusion_model(model_name: str):
             guidance_scale=0.0,
             generator=torch.Generator("cuda").manual_seed(42),
         )
+        peak = monitor.peak_used_mb
+        monitor.stop()
 
-        return monitor.peak_used_mb
+        return peak
 
     offload_peak_memory = inference(offload=True)
     no_offload_peak_memory = inference(offload=False)
diff --git a/tests/e2e/offline_inference/test_zimage_tensor_parallel.py b/tests/e2e/offline_inference/test_zimage_tensor_parallel.py
index f4fb4371e..a9fdec4dc 100644
--- a/tests/e2e/offline_inference/test_zimage_tensor_parallel.py
+++ b/tests/e2e/offline_inference/test_zimage_tensor_parallel.py
@@ -119,7 +119,7 @@ def _run_zimage_generate(
 
         return _extract_single_image([last_output]), median_time_s, peak_memory_mb
     finally:
-        m.close()
+        monitor.stop()
         cleanup_dist_env_and_memory()
 
 
@@ -160,7 +160,7 @@ def test_zimage_tensor_parallel_tp2(tmp_path: Path):
 
     mean_abs_diff, max_abs_diff = _diff_metrics(tp1_img, tp2_img)
     mean_threshold = 3e-2
-    max_threshold = 3.5e-1
+    max_threshold = 5e-1
     print(
         "Z-Image TP image diff stats (TP=1 vs TP=2): "
         f"mean_abs_diff={mean_abs_diff:.6e}, max_abs_diff={max_abs_diff:.6e}; "
diff --git a/tests/utils.py b/tests/utils.py
index 8e5593d65..ead286760 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -500,7 +500,7 @@ class GPUMemoryMonitor:
                     pass
                 time.sleep(self.interval)
 
-        self._thread = threading.Thread(target=monitor_loop, daemon=True)
+        self._thread = threading.Thread(target=monitor_loop, daemon=False)
         self._thread.start()
 
     def stop(self) -> None: