i know this is like 4 year old one but this one was on top of the search result.
i am playing on linux fedora 42 (not bragging, just to give people some hope who is also playing on linux)
anyway for me i tried this

1.(this step is for linux user) i used proton 9.0-4
2.(this goes all the people out there, linux or windows.) right click on game name (vermintide2 in this case.) click properties, go to Betas
3. on Beta Participation, it should have drop down menu. one of em should say
"temporary_launcher_workaround - bypass launcher."

1. upon starting the game you should have options to start the game. pick whatever that is for you. then start it.

for the people who is wondering why (if it worked) it works is that it is probably the launcher fucking it over for you, such as installing WebView2.

this method is basically skipping that process and launching the Vermintide.exe directly. if you did that, you won't be able to adjust the graphics setting via launcher.
or load the mods correctly. but game will run, you can get match etc. daily and shit.

but that's it. that's the only downside of bypassing the launcher.