For (certain) individual's to claim that (only) because they've studied, and possibly even received a Shodan (while on active duty) in Okinawa, is not a validation of what-ever they may claim (knowledge wise).
So, are these individual's Faux? (Fake?), no I don't necessarily believe so. Are they possibly less knowledgeable?... possibly (I'm sure that would need to be decided on a case by case basis). The only things that would influence my own decision (in regards to studying from them) would be how long were they there, whom did they study with while there, and what other instruction have they received (and from whom?). Basically, no different from anyone else out there teaching today.