I'm probably going to regret jumping into the middle of this, but here goes...

First off, to OP, I'm sorry. I have an autistic cousin and have served as caretaker at times, including during travel. I know your struggle, believe me. It doesn't seem like you did anything wrong.

However, having said that, UA technically didn't do anything "wrong" either. If you have status you are allowed to 'UG' a companion to E+ but that companion is technically supposed to be on a paid itin. No, I cannot quote the rule. Nor can I provide the website that shows this to be the case. I am speaking based on experience talking with many people and reading many threads on this forum. If your companion (in this case your child) is on an award ticket, he or she is not entitled to free E+. It seems that the agent noticed this and decided to move the kids back to E-. I would further hazard a guess that since they are (presumably) not able to sit by themselves, you were moved back too.

Again, I want to disclaim any partisanship. I'm not trying to attack the OP or defend UA, nor vice versa. I'm simply trying to point out that this is just an example of them having a rule and following it, and us (as the customers) not necessarily liking it. I'm truly sorry that it didn't work out as you'd hoped.

P.S. I understand that the OP may have gotten away with 'linking' paid and award tix until now, but that is not generally how things work. This just happened to be one of those times someone scored a freebie and was 'caught.'