Write or wrong. Oh my g-d. I know exactly what you mean and I unfortunately know too many roshei yeshiva and principals like that.
We are living in a world with priorities so wrong and all the wrong people at all the wrong positions.
I would write a very sharp letter to the r”y, and then PULL MY SON from that Yeshiva.
There are many small Yeshivos catering to your son’s needs. Many Yeshivahs that take each child as an individual, and work with them according to their needs. They have professional Mechanchim running the place.
It’s worth for you to begin exploring your options and placing your son where he really belongs, even if it isn’t considered a “top” Yeshiva.
Hatzlacha.