Can't progress because character won't move

Hi all - I posted about this a month or so ago so I doubt there's been any great breakthrough, but I'm going to try again anyway. I tried uninstalling/reinstalling the game again (with CC Cleaner in the middle) and still have no luck - I really am out of ideas and I can't find that anyone else has had the same problem. Help?

There is one spot in the Arbor Wilds where I can't move forward. (It's after fighting a battle in the river, on the way to the second barricade - you come out of the river onto a path.) I start to run up the path, and the controlled character just freezes. Not the whole game - I can switch to a different character and get this one back, move the camera and so on - but can't move forward. At all.

Video of what I mean is here.

Switching to tactics mode and trying to 'move to point' doesn't work either. (It does for a very few steps, but then the character flashes back to the water)

Switching to a different character in this party doesn't work.

I loaded an old save from a character I've already completed the game with, so I KNOW I made it past that point, but that character also freezes, the same way, in the same spot. (Which means even if I gave up this progress and started all over, it would probably not work. I can live with losing the rest of this game, but am not excited about never being able to make it to the finale again!)

Yes, I have mods - just a few aesthetic things that were there the last time I got through. Removing them does not solve the problem.

Drivers are updated.

Repairing the game didn't work.

Uninstalling and reinstalling the game didn't work. (The video is from AFTER having done all this.)

I don't have the Discord overlay, which apparently sometimes does weird things.

ADDED 22.1.22: I tried uninstalling, cleaning the registry, and reinstalling the game again. Still no luck

Hastebin specs are here.

I will say this isn't the same computer I started playing on; I had to reinstall everything onto a new machine about a year ago, so it's possible I messed something up there, but I've been playing since then and this is the first and only time anything has gone wrong. It seems like a really weird error to have. Performance thing? Random glitch? Is there a debugger or something I can use to jump ahead in the plot? I'd really like to move on from this one teensy area and I've been trying to find a fix for this for days.

Anyone have any advice? Please?