Yikes!! Your principal sounds horrible! I wish I had something to useful for you, except hugs. My DS has anxiety too, and it doesn't always look like people think it should look.
How old is your DS? Did he cooperate with the tester beyond the inattentiveness? If he was extremely anxious it could have resulted in him "blanking out" (that's how anxiety affects me).
I don't have any suggestions for how to deal with a horrible principal, unfortunately, especially when they won't even talk to the psychologist. How is your son's teacher this year?
Anyway, I hope you find some answers. This is a great place to find them
