I've tried opening this with every media player I have as well as Handbrake, nothing handles this file.
It was produced by Swivel. Is Swivel in error? Can it be fixed in avidemux?
It's an 700*700 15fps 8 second long uncompressed video, which doesn't seem to make sense given the filesize either.
https://we.tl/t-bPtX7b6ut0
Basically, open the file in a hex editor, find the both "BGR " (0x42 0x47 0x52 0x18 – no idea why 0x18 instead of 0x20) strings very close to the beginning of the file and replace them with zeros (0x00 0x00 0x00 0x00), save changes. After that, the file should be universally usable. The picture looks flipped, but this probably needs to be worked around in the editing pipeline.