its probably been said lots in here, but I couldn't find anything when I went looking in my search results until I read through some comments on a post.

Uninstall everything, Fluffy mod manager, RE3.
Right click game from library, manage game,
Click on Betas, Beta Participation - Selection DC11_non-rt -dx11_non-rt.
Reinstall everything, download a new copy of Fluffy mod manager, tell it where the folder is and install your mods as normal.

This seems to work fine as of July 2024. Spent an age trying to get it to run till someone mentioned a clean install. Worked Straight away after clean install.