The list looks pretty typical, except I don't see any Occupational Therapist (OT)/PT type assessment. I find it very odd that the speech delay tested on the low end of the chronological discrepancies yet they singled that out as the only area he qualified in. Did you mention anything about thinki8ng you'd continue with private therapy or private preschool that might have given them the idea they wouldn't need to provide services?
Sheila and/or Martie will likely have additional advice, but if this were me, I would contact his developmental pediatrician you mentioned in this thread. Make an appointment if you have to. Tell him/her that he has been denied all services except for speech and ask for a letter to be written specifying services including preschool. The school still may deny the services but they have to take in into consideration and sometimes doctors hold considerable leverage. Even if you agree the Pervasive Developmental Disorder (PDD) diagnosis isn't accurate, there are still delays in most areas that need addressing.