This teacher is either crazy or senile and covering her tracks, or both.
The other thing to consider is that a student has hacked into the teacher’s email and is doing this. Probably not too likely, but keep it in the back of your mind.
I would also do a face-to-face with the principal, and record the conversation.
If this is the teacher truly communicating this stuff though, this person is mentally unstable. Go ahead and disrupt your daughter’s schedule, whatever it takes to get her away from this situation.
Yes.