Modded Multiplayer Joining Bug

My friend and I are trying to start a modded game together, we have spent hours trying to get it to work. Every time she tries to join her load percentage stops at 81%, lags, hits 83%, and then immediately boots her out to the title screen. Two times we have tried having her host instead, the first time my game crashed and the second hers crashed.

Previously, we had Unique Tav and the level 20 mod installed. After seeing people mention those mods as possible issues, we reinstalled them both, along with a few other mods we had installed ages ago just to be safe.

We have tried pretty much everything, including removing all of our saves and turning off steam cloud for the game and switching mod managers from Vortex to BG3MM. Does anyone have any idea what can be done?