Science isn't always an expensive endeavor. Certainly checking in with clients a few years after and comparing outcomes with a control group could be done with volunteers. Setting up a blind can be done with basic survey tools which are available at low cost.
The expensive parts of this research are getting facilities and people willing to take an untested treatment. But he already has both those, so I really can only attribute the lack of scientific evaluation to a lack of will to do it.
I'm not saying that's a bad thing -- unethical and/or misguided researchers have actively harmed their subjects too many times in the past. Nonetheless, it's something that people who haven't done human subjects research often overlook, and something that can add a huge amount of expense and delay.
If you're doing generic CS research* the worst that usually happens is that you have to reboot. We can't reboot people, at least not yet. :-)
*If you're doing research on, say, human computer interaction, you generally do have to get human subjects approval, but not usually for compilers, algorithms, or the like.
Edit: "people willing to take an untested treatment"
That's exactly the rub. The potential subjects for something like this are what's known in the jargon as a "vulnerable group". You have to be very, very sure (and be able to convince a skeptical oversight committee) that your subjects are, in fact, giving their active and informed consent for an experimental treatment. That's quite hard to do for people with severe psychological problems (again, rightly so... some of the abuses of the past make for sobering reading).
I think the reason he hasn't done studies isn't because of lack of funding, it's because scientifically validating his claims isn't a priority.
You don't need institutions to prove your hypothesis, you need evidence.
I'll add that I think the reason he hasn't performed studies on the technique isn't lack of funding, but that validating his claims isn't a priority for him.
His background only makes me believe more firmly that evidence is not a priority for him.