It is pretty much a given that you may not be a "Zero Club" member if you still have a prostate, no matter what has been done to it. Whatever prostate tissue remains will generate some PSA.
On the other hand, if your PSA is within the objective of the treatment you had, and is stable or declining, I think the guys will let you pull up to the bar. It is, after all, just a way to celebrate the guys who have good numbers at present.
Those of us with no prostate, but a rocketing PSA, have to just get up and quietly leave a seat for the new guys until HT kicks in
But I will be back -
Have trimix, will ....