Turbo or factory EBCS problem?

I'm having an issue with low boost on my MS6, my accessport is only logging ~10 psi max at WOT, when I first got the car it was easily hitting 15+psi.
Absolutely no boost leaks that I can find, just went over the car yesterday, bolts holding the turbo to the manifold where very loose, tightened those up, still no fix.

I'm pretty sure my factory EBCS isn't working at all (it's plumbed correctly), but I just want to make sure that's it, is there anything I can check in my logs to know for sure? Or should I just throw on a aftermarket EBCS and see if that fixes it?

Car has 164k
My motor itself has ~12k (ZZB in cylinder 4, 45 days after purchase, dealer replaced it) shortly after that this problem started.
K04 has the full 164k as far as I know, pulls hard and doesn't suffer from any smoking, minimal shaft play.

Anything else I could be missing?

 

In your logs, your wastegate duty cycles might give you a good idea of what your ECU is trying to do with the boost control.

 

Swapped out ebcs, boosting issue fixed, grimmspeed 2 port set up for now, still swapping turbo out this weekend though.