So I've been thinking about the glitch and wondered what exactly could effect Mario's state such that a strange case could occur. Certainly by now many people have tried to replicate this following the original movie, and since the bounty is still unclaimed there must be something else at work here.
Then I was watching one of pannenkoek's other videos about extreme coin RNG:
https://www.youtube.com/watch?v=7PXiEbvZoTs
At ~1:32 I noticed a coin clipping off of the ice structure in the background in a weird way. It reminded me of the Bob-omb's coin in this glitch.
I wonder if the coin is going off the edge just as mario is landing, and as the game processing the coin clipping around the corner, it leaves some flag set that later effects Mario as he hits the floor.
I definitely lack the technical knowledge of SM64 to test this, so this might be as far as I go, but I wonder if anyone has any thoughts on this? It's the only thing I can think of with a sufficiently small enough probability that the glitch is this super rare, and hasn't been reproduced even while mimicking the movie quite closely.