momto3girls, I'm sorry to hear that this is happening at such a bad time for your family. I think the best you can do is super child proof the room, so that she will be safe no matter what she tries to do during the terror, and then be there for her emotionally. I would probably move into the room with her, if it was me; its just my style - I like to "see" as much as possible - and the simpliest answer in my world. But whether or not that would be your answer is up to you.
_________________
Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).