it may be, but i honestly doubt that is the case because your boost went to the exact same thing when you removed all boost control whatsoever. even with the stock inlet on a baby vf, with the boost control completely removed you can easily spike to over 25psi in 3rd. i think that would be a factor as to why you can't target really high boost, but 22psi should be a cake-walk with the wastegate flapper wired shut.
my guess is still a boost leak or the wastegate is stuck open some...who knows though...definitely keep us posted. i am curious to see what your findings are.