......etc, etc, etc
The final week of the season, the HC wasn't at the Saturday games and the AC told me that he wasn't going to pitch my DD because all she did was strike everyone out.
Let me get this straight... your DD doesn't get to pitch because she is too good for the level she is playing.
Well it is pretty simple - she is on the wrong team. It doesn't matter at this age whether she finds a better 10U team or just finds an appropriate older 12U team who needs here. Maybe it is inconvenient for you - you are going to have to figure it out. Older team may be an easier option for you based on your posts.
If you want to stay on this team you are going to talk to the coaches. There has to be some sort of balance in developing players and there is plenty of games to pitch. It is possible that your coaches realize that your DD is not long for this team, know she is going to move on and are trying to find out who on the team are going to be their pitchers when your DD does move on. That is a weird way to go about it - most travel coaches would be pitching your DD as much as is reasonable.