Why can't the Dashboard 'Integration Docker' / 'Docker Logs' find 'error' messages?

The error log message is “2024-03-04 17:15:55 UTC - ERROR - process_one_video-311714: Unable to serialize to JSON: {‘doc’: {‘video_status’: ‘downloaded’, ‘processing_error’: None, ‘video_info’: VideoInfo(width=1920, height=1080, length_ms=1644366, fps=30.0, total_frames=49331), ‘utc_updated’: datetime.datetime(2024, 3, 4, 17, 15, 55, 173306)}} (type: dict)”

Why can’t the Dashboard ‘Integration Docker’ / ‘Docker Logs’ find ‘error’ messages?