I believe it is an Intervention service, rather than a medical facility.
Family First Intervention - family-intervention.com
They did the intervention at his home in GA and then accompanied him to the rehab facility that they work with in CA.
In doing some research I found this comment on rehabilitationguide.com that said
"All expenses that are needed in order for someone to help recover from a substance addiction are covered under §213(d)(1)(A) of the tax code. "
So I think it may be a bit of a gray area.