Do they have any further information on the IQ scores other than that the composite/total number was average? I'd expect to see some significant scatter in a 2e child whereas a child with a truly average IQ who achieves highly due to good work ethic, etc. would more likely have a lot or most of the scores falling in the average range throughout the test.
I have a 2e child and part of what you say at the end resonates with me and part not, but of course not all 2e kids look alike. I, too, worry about pace for my 2e kid as she progresses through school not b/c she is slow, but b/c she reads very slowly, it gives her headaches, and I worry that she'll have a hard time keeping up with the reading quantity in high school when she gets there. OTOH, abstract reasoning isn't something I worry about at all b/c that is a very strong area. I don't know if lower abstract reasoning is typical in 2e or if you're dealing with a different type of 2e than are we.
If there really is a 2e issue, I don't think that figuring it out is moot just b/c she can compensate. Mine can too.