I thought about martial arts since DD also seems ODD - but I was afraid she'd use what she learned to hurt her twin, DS! (Same reason I won't enroll him, LOL, though he could really use it too.) Keep up posted on how that goes.
That stinks about gymnastics
. I don't know how some people decide to work with children. It blows my mind how they treat any remotely challenging child. Ugh so sorry. Best,