Those teachers sound like they are focused on seeing everything as connected to autism (which, I’d kind of give them, considering pervasive) and therefore to be pathologized (which is where I go OH NO YOU DON’T.) Favorite foods change. Stimming is great. Speech is overemphasized.
As an autistic adult who uses AAC part time (I sound pretty darn fluent when my speech is at its best, but that’s not all the time and sometimes speech isn’t happening at all), I really appreciate how you got him the AAC. It’s super useful even if speech sometimes works.