Two factors to consider...
1) what were the FIRST three years like? we know the last 5 were awful, but before that? Because... those first three years are when a child learns how to trust and develop relationships with people. If those were even "reasonable", the long-term prognosis is better.
2) Reactive Attachment Disorder (RAD) is a spectrum. A child can have disordered attachment and not be at the far end of the spectrum.
You're definitely dealing with a complex kid (like most of us here!). Don't be content with one diagnosis... it may take several. He may be Autism Spectrum Disorders (ASD) plus somewhere on the Reactive Attachment Disorder (RAD) spectrum... and maybe some health issues thrown in to boot.
