ffmpeg -i source.mkv -i suspect.mkv -filter_complex "blend=all_mode=difference" diff_output.mkv
I saw these claims before but still have not found someone to show a diff or post the source for comparison. It would be interesting.
Edit: The changes made by the ai are a lot more vissible in the higher quality video uploaded to patreon: https://www.patreon.com/posts/136994036 (this was also linked in the pinned comment on the youtube video)