I don’t believe I suggested you “shop around”.
I suggested you talk to your pastor. Your pastor, is the legitimate authority over sacramental preparation. The bishop is they ordinary minister of the sacrament, and he may or may not have set specific standards for the military archdiocese. In absence of diocesan standards, it is the pastor who makes such decisions.
Talk to the pastor-- whoever the military chaplain is. It is not within the religious education director’s authority to deny sacramental preparation done by the parents, nor to delay or deny access to the sacraments.
It’s the pastor’s decision as to whether or not the candidate is ready for the sacrament. So again, I suggest an interview between your son and the pastor, not your son and anyone else.
“Youth group” is not a canonical requirement for reception of the sacrament of confirmation and it cannot be denied your son for that reason. Contact
stjosephcanonlaw.com/ for guidance.