Could an autism diagnosis be wrong? many other professionals are questioning the dx. also, he did not qualify for the preschool disability program.

Yes: Any diagnosis can be wrong. Mild cases of ad can be misdiagnosed as other things. And other conditions can be misdiagnosed as ad. Who made the diagnosis? Your pediatrician? The school? A developmental pediatrician? A psychiatrist? A pediatric neurologist?

Not uncommon: Sometimes we have to observe a child in different ways. Our neuropsychologist sees patients first & gets the best out of them on standardized tests. Then they see me (db pede) when they're tired, but they've had a snack. With parental permission, i push the buttons that bring out autistic behaviors, if there. Atypicality that we see that way may not fulfill school eligibility guidelines.

Go with your heart: Autism is not a definite disease. It is a description of behaviors. Many children have autistic behaviors - some only now and then. The challenge is to be more consistently normal in behavior. If you believe he is bright and normal, he will believe he is bright and normal. He may not need special services, just good direction and belief in himself.