I have two thoughts based on what you've posted thus far. Was comprehension a low outlier on the Verbal index of the WISC? It definitely was for my dd. I've been told that a low comprehension score is more common in ADD as well as ASD. My dd is very, very socially aware -- to the point that she trims herself to fit in so well that almost no one knows the true kiddo -- and I am pretty confident that she is not on the autism spectrum. However, your last post in which you mention that your dd's behavior appeared young and that she does things that scare off other kids had me wondering if you'd considered aspergers.
I found Dr. Webb's book, Misdiagnosis & Dual diagnoses of gifted children & adults, to be really helpful in seeing whether my dd was 2e or just underperforming due to poor fit. She was the opposite of every single thing he listed for a gifted child who didn't have ADD. I believe that book also has a chapter on ASD if that is something to rule out as well.
I was coming to post something very much like this. (Actually, I was coming to see what the answers were, because thought I had posted questions about it last night, but apparently not...my post must have vanished into the ether.)
Did the evaluator administer the GADS or ADOS?