check meta path if enabled

app.py

@@ -23,7 +23,7 @@ def retrieve_results(selected_dataset, selected_sequence, selected_models, selec
 
     meta_enabled = False
     meta_path = get_meta_path(base_data_dir, selected_dataset, selected_sequence)
-    if not os.path.isfile(meta_path):
+    if meta_enabled and not os.path.isfile(meta_path):
         raise ValueError("Meta file not found: {}".format(meta_path))
 
     gt_only_viz = [viz for viz in selected_visualizations if viz['viz_type'] == 'gt_only']