Thank you so much for all of your comments on both threads, Eldertree.
I called the insurance company and finally got far enough up the management chain to be told that we can have a second opinion, which my son is also willing to do. I meet next week alone with the original psychiatrist who referred him for testing, so I'll be free to be candid without my son having to hear all I have to say.
The slow processing score combined with the comment about "overintellectualizing" is notable. Mostly what it says is "the kid took too long because he was thinking too much about it". Which basically says that the tester has very poor skills with gifted kids, and not a whole lot else.
Executive function issues combined with some of the other things noted may indicate ADHD (or something similar) compensated for by a bright kid. Or you may just want to look at this whole test as your insurance company's money well wasted, and start afresh elsewhere.