J.S.
My third is spectrum, just like his dad but whatever. If you are right and your husband is the tree to your son's apple he will blindly call every bluff. Don't ask me why, but they do. He will, and it sounds like is, thinking the GAL is trying to trick him. There is not much you can do. We got lucky, our GAL had a daughter in school with our older daughter. Um, how do I nicely put this, private school, top in the city, most parents are pretty wealthy. Anyway because of this my ex saw the GAL as a peer and actually listened to him. If that hadn't been the case I probably would have killed him long before the divorce was final.
See his attorney knew he could just keep going, keep getting paid damn near forever so he encouraged my ex to fight where there was no fight. The GAL managed to shut his lawyer down so to speak and get through to my ex.
What was the GAL's parenting plan like that a judge would not order it? Also have you considered that if the GAL cannot sway a judge that their parenting plan is best they probably cannot sway a judge to give you full custody? Judges generally don't care if you cannot communicate. What the end up doing is spelling it all out and ordering all exchanges be done at the police station. That doesn't sound good for the kids either.
One of the hardest things to swallow during my divorce is that justice is not just blind, it is dumb too. The most shocking thing was I never lied, he always lied, yet the judge believed him. See judges don't know you any better than that psychologist will know your kids. Think about what superficial things your judge will base credibility on. Just saying this so you understand you quite possibly will do no better in court than him. Right or wrong, what is best for the kids or not, truth or lies, they mean nothing in court! What matters only is who the judge believes and you are just as well off flipping a coin.
Oh wow, they tried to push the one kid thing on me and I fought it and won that battle! We are a family you don't separate us! So sorry, I agree with your husband on that one!
At the time of our divorce my younger daughter was five, my son seven. Eight years later they are both thriving. Daughter grew just fine, son learned to control himself. I can assure you if we went tit for tat our boys have the same diagnosis. No one just has spectrum.
It is bad enough when you divorce, to split up the kids too, that is insanity. It may be easier on the parents but what is easier for the parents is unimportant.