I suspect diving with CP is going to be far beyond merely ticking boxes on someone's "don't sue me" waiver.
The only reasonable way I see to do it is through diveheart. If he can get them engaged... I don't know how diveheart works, but unless it's a charity that's paying for everything - this is likely to be an expensive endeavor. Consider that if you're in perfect health you're looking at $300 plus gear, plus boat rides, and since he's landlocked that also means a road trip or airplane ride and lodging at his chosen destination. The photos and videos I've seen of diveheart dives seem to include a lot of support staff. I wouldn't be surprised if you had to do a private charter each time.
Diving is expensive even for those of us fortunate enough to live in Florida (or California or some other dive destination).
As
@diversteve said, if $15 is even a small concern this isn't likely to happen.
Could possibly be solved with a well promoted gofundme or other online crowdfunding campaign.