Hi fsudiver,
I am a PADI IDCS Inst. and a HSA, and IAHD Inst. I have been working with divers with disabilities for over nine years, and you are right you need to find an Inst. who has special training with people with disabilities. There are a lot of Inst. who think they can certify anyone. But it does take a special skill to be patient enough to give the time it takes to certify someone with special needs. Only a IAHD or HSA Inst. can certify someone who cannot pass all the requirements needed to pass a PADI, or NAUI or any other certifying agency course. If I can be of any futher help let me know. The US Headquarters for IAHD is in Key Largo, FL at Capt. Slates Atlantis Dive Center
http://www.captainslate.com