This is the best parental concern letter I’ve ever seen! They are bringing in the supervisor because you have pointed out that they are breaking the law-they are denying him FAPE. They are violating FAPE in so many ways. He’s not in the Least Restrictive Environment LRE. His IEP is not written to address needs. Did they actually evaluate him when he started school? Because that must have been incomprehensible and inappropriate. He’s not receiving the same education as his non disabled peers.
You very eloquently and unknowingly accused them of violating FAPE which is the biggest no-no. In short, you scared the $&@“ out of them. Bravo!