There is no doubt there is something wrong with the coaches. OP said multiple girls have noticed over multiple years.
There is no doubt that whatever is wrong with the coaches, it is NOT such a big deal that the AD or the parents can do anything about it. It is not big enough to fire them especially since they can back each other up when questioned.
The OP seems to realize all this and has been asking his daughter to deal with it all season. Now he is looking for a little relief. As an adult, he should realize there is no such thing.
If what the OP says is true, everything is exactly how the coaches want it to be because it is their team and they set it up this way. Why the OP thought asking them would change anything since the have worked long and hard to create this atmosphere is unknown.
All the OP can have his daughter do is to ask for things that will help her that the coaches have not considered yet. It might help if it wasn't even his daughter asking. For example, if his daughter's best friend on the team asked to train/ride/room with her for cheering purposes.
The coaches may think this is validation of them as coaches for someone to want to spend extra time with them.