The video is corrupt until 04:23:38 (+ a few frames); that is, all but the last 4 hours of the video are corrupt. The corruption appears to prevent playback with some programs, but I was able to successfully playback using VLC (specifically 3.0.11 Vetinari / jenkins@ee165b7cae4d Jun 4 2020 15:48:20). I was _not_ able to successfully trim the corrupt portion with FFmpeg; the warnings it logs suggest the corruption is confusing it, although also I am not an experienced FFmpeg user so the problem could instead be user error. The non-corrupt portion of the video matches the length of the audio (04:00:01), and the audio appears to be in sync for these last 4 hours.