We don't have direct experience with moving mid-year, but have several schoolmates and friends who have done so. It was a relief for all of them when the move occurred. The children and parents were all happier. You've given this school plenty of chances.
Requiring children to re-take a year of 1st grade math just because they have a new curriculum is ridiculous. They've mastered the material. I would be out of there as quickly as possible. Search for a school where the administration has a record of moving kids to different grades for different subjects when needed. Your DD obviously needs to be in 2nd grade math this year, and an administration who is currently accelerating some children within the school will serve your needs best.
