what do you mean the line didnt leak when you plugged it up? Inside of that line there is a check valve. If you can blow in it both ways its bad. If you blow in it going towards the brake booster and it doesnt let u blow through it its good. Sounds like its bad anyways because it shouldnt have let boost get to the brake booster when you initially did the test. Im sure you can find a check valve somewhere and just run it inline with that hose.

Ok so the brake booster isnt suppose to get boost?

Not a single bit of boost. There is a reason for that check valve.