I think the problem arises when you engage the first group of Skeevers. There are some down in the tunnel and they seem unable to get up to fight you, and most people never notice them, so they remain unkilled. This means that the player is always in combat and thus cannot use things like doors.

Anyway, what you can do when the bug appears is to just jump around like an idiot, sprint, crouch (bonus points for being Hidden), roll dodge, etc. At some point you should be able to walk through it. It's important that, if anyone who's already gone through attacks the boss there, you won't be able to pass until that boss is dead, so remember to wait past the door until everyone gets through before engaging anyone.

EDIT: It doesn't seem like I can delete this comment. I misread the original post and assumed that you're talking about a bug later on in the dungeon. If the doors don't open (which never happened to me, to be honest, they always open eventually), then just reset the dungeon. You've only killed two groups of mobs and one mini-boss, most groups that are even slightly competent take no more than 4 minutes to do that, so it's not the end of the world to repeat it

Yeah crouch to hidden is how I do it, same with Volenfell.