Your misunderstanding what the dual reference gate does. A Tial gate like you have is a very good gate for limiting boost. The ED/JGS/dual reference style gate is not for limiting boost. What it is doing is limit inefficiency. It limits the how much higher the drive pressure is over the boost pressure regardless of overall boost.
It could also be 10psi regulated from the drive pressure, it does not matter when you're working based on a pressure differential. I prefer the boost side to keep the soot out of the system.