@Dan ******
there is no such list as far as I can establish
The various governing bodies who license muay thai are
1. Sports authority of Thailand
2. Board of Boxing Sport
3. Ministry of Education
It is also required that a gym us a registered Ltd Company liable for tax.
The Education visa requires a gym to be a licensed school but this is not the case for the DTV.
Find a gym that has all 4 licenses and it will be 0lain sailing but if you already have a gym see what license or licenses they hold and try and match it with an embassy requirements.