a missing pill would drop the boost - but not down to gate pressure as the 2port solenoid would still be able to raise you up above that. It's also possible the ECU is in limp mode - when it hears enough knock it pulls back timing to a point where it also turns off the boost solenoid to drop the boost down to try and keep the engine alive.
If you don't have a pill handy, take yourself off to the local welding shop and pickup a 1.1mm welding tip. With a bit of hot water to soften the pipe you'll be able to force it into your fancy hose. If you still have boost issues after that you should get the laptop out and check things over it should be very easy to check the IAM value and see what if it's dropped.