I think this all started with the Todd Rogers Atari Dragster WR proving to be impossible (using computer controlled inputs, and perfect start moments). Naturally the Billy Mitchell tape would prove to be another project for YT sleuths.
The tape has screens that load more like a mame screen loads, and contained artifacts ('girder tails') that apparently only show up when running mame hardware. There is discussion about what versions of mame existed then, and how the differences may be noticed on screen.
I really hope with this live million point game that he can begin to rebuild some of that lost reputation, at least with some people in that community. He's a nice guy and I consider myself a fan despite what he might've done with that tape.