Specifically what is he doing that is causing the psychologist to place him at 2 years advanced cognitively? I had a child that started reading/spelling when he was 28 months and could name most of the countries and their capitals by age 5 so I've dealt with this.
For bedtime, you might ask his doctors about Meltatonin. Parents here have had good success with it, most of them without side effects. Do ask your doctors though as there is at least one seizure medication it can't be used with. GNC sells a child's formula.
Also, I thought to mention Sensory Integration Dysfunction. It can really kick up around age 3 as children become more aware of their surroundings and can majorly contribute to anxiety and meltdowns. Normal sensory input to us can be all out assault to a child with Sensory Integration Disorder (SID).
http://www.tsbvi.edu/seehear/fall97/sensory.htm
