Thats not enough boost for stage2 thats only just over a bar? 18psi? I would check all boost and vacuum pipes for splits.
Chech DV to.
get nothing on vag com??
Or replace it with a catch can
Yes that's the problem they need to be joined together.
as said before. pressure test your system as per the guides on here, or go to a garage and get it done for you. There are so many potential places for leaks. PCV is unlikely to be the cause IMO, you wouldn't lose that much boost.
To check MAF, unplug it and go for a run, see how it feels. Don't leave it unplugged for too long tho.