what form of boost control does it have then??

i'm no expert, but my understanding is the boost pressure from the compressor housing runs through the C port of the amal valve, and is bled off through the R port until full boost is reached, when it then goes through the W port and forces the actuator rod to open the wastegate,

so i don't see how your wastegate is controlled

of course i wait for a more skilled reply to help you