Again, this wouldn't be my decision, and I don't see why ( apart from just bad faith arguing) you are trying to pretend it is.
I, and others, have already set our accommodations thag could be used in terms of sport.
No you haven't set out any accommodations. Members of your own team objecting about the boy pushing them down the pecking order. Opposition refusing to play because you have a male on your team.
What are you suggesting should happen? What is the rule you go by?
Reading between the lines what you seem to be saying what I am gathering is if the boy isn't big and strong or very good at football you play them because it is more defendable? I am not putting words in your mouth, just guessing because your are not answering. Clarify if you have answers.
You are the one pushing for boys in girls sports so surely you have a better blueprint for how it works in practice. You might want to think about this ridiculous agenda you are pushing if you haven't thought is out. A committee meeting above your pay grade to decide who gets discriminated against for each case doesn't cut it.

