@MiniMum97 - my ds is 14. He absolutely still can't be relied on to exit a changing room with anything resembling the same clothes he went in with.
He's on his school's register as both G&T & as having complex needs.
I think we'd all agree he doesn't get a pass to get changed with me in a communal female change, right? & that's been the case since he was 8.
It's got better - at 7 he would not have been able to cope at all. At 14 (& probably into adulthood) he needs a private space away from everyone else & a checklist on his phone. Plus everyone accepting that he's going to take noticeably longer than everyone else.
My reasonable adjustment is that he gets let off kit detentions for school PE/swimming & I buy him a lot more pants & socks than I'd choose to. (& lots of other adjustments, but since we're talking about changing rooms...)
There absolutely needs to be better provision for disabled changing for anyone of any age who can't independently manage the whole 'clothes off, kit on, activity, kit off, clothes on' business. But past the pool's cut off age, that adjustment is NOT reasonably 'budge up ladies, X needs to get changed with his mum'.
& I totally accept that OP's ds evidently, from her posts, needs considerably more support than mine!
Just that the solution to 'boy with additional changing needs' CANNOT, long term, be 'oh that's mum's job, off to the ladies' change with you both'. Undignified & inappropriate.