Loss of interest in soccer

My son(autistic 10 year old) was very on the fence about joining soccer this season since most of the boys he had been playing with since first grade were not going to be on the team this season. He ultimately made the decision to sign up. Money is tight in our house. I saved for the registration and outfitted him with new cleats and shin guards since he’s grown so much this past year. Now that we are two games into the season he is saying he doesn’t want to play anymore. I told him that he made a commitment to this team and he doesn’t have to play, and he needs to show up to support them. His dad(my ex)is saying why waste the energy taking him to an activity he doesn’t want to do. I said that’s fine for next season, I’ll find him an activity he does want to do, and for this season since we are already committed, I think it’s important to see it through. I just want to do the right thing. Should I let my son just quit? Or should we see the season through as the team cheerleader?