I've checked around but didn't see this anywhere, sorry if I missed it.

It looks really clear to me that in the Game last year, Connor Stallions was directly affecting playcalls from the UM staff at times, and it's visible on the broadcast

I think I did the embed right, but start at the 27:45 mark of the video, on the 2nd and 3rd down in the 1st quarter for OSU. Both times, the cameras show Stallions saying something to the DC, and the DC then calling for a play that is signaled to the defense. Incidentally, both plays work in the defense's favor.

For the 2nd down play, after Stallions relays the signal from OSU to the DC, the DC says "blitz" a few times, and then the run blitz goes to the exact right spot to stop the play. This is kind of hilarious to me - it's clear how highly involved Stallions was in affecting the game, even though UM's whole strategy right now is to paint him as a lone actor.