Yeah, vermiculite is fucking miserable. I’m half tempted just to have the entire thing cleaned out and start over. If only I were made of money.
The situation with the vapor barrier is already there. I think it’s wrong and needs to go, but I could be wrong. The thing I definitely know I shouldn’t do is add anything on top of it.
As for air sealing. I’m probably going to chase down every singe penetration, but there are a handful that really need attention and won’t be challenging.