B Mom 25 this is a tough issue. I hope it works out, and that your son and the coach can resolve or at least put their issues behind them.
FWIW, my son garnered his interest and offer from the Travel coach who had the contact with the Head Coach where my son is headed this fall. He not the HS Coach assisted with his recruitment as he does with the boys in his program. Even then , the Coach called his HS Coach and exchanged emails with the HS Asst Coach\ Pitching Coach, they do their due diligence and hoping they won't make contact will not work.
Only 1 solution , son has to eat some humble pie, lead by example and get through the year. If he really wants to play at the next level he will do it.
Good luck and keep us posted on how it works out.