I have seen Dr. Sheila Bastien in Berkley twice. Both times her report made a huge difference for me in getting my LTD benefits. She knows a ton about CFS and is probably the pre-eminent expert in the Neuropsych field regarding CFS.
I second Dr. Bastien in Berkley CA. She helped me get LTD benefits. I got a neuropsych report from her as well as a SPECT scan she ordered. She knows a lot about CFS. You should also look into having the University of Pacific exercise test if you can. Even if you don't go there to do it, see if your doctor can call them and get the protocol and then have it done in your doctors office. It very clearly objectifies the energy deficit in CFS.