I read through this thread before, a couple times before in fact. But I can't recall right this second all of the points presented, but I'll try to recall what I can.
I'm sorry OP, I don't know of the specific encounter you're referring to. I wish I did, I'd be very curious to know more about it. The fact is though, it's not uncommon for that to happen, fighters going to other countries to fight different style artists. The problem arises in the home turf advantage.
Next I'll mention that I'm of the mindset that it's that artist, not the art.
There's so much Muay Thai-lovin' goin' on in this thread though, I think I'll have to put down a little bit in favor of kung fu.
Bao Li Gao is a Chinese Sanshou fighter who has beaten Thai fighters in Bangkok. He also has a MMA record of 4-0 in Art of War, with his arts since he started MMA including Sanshou, Shuai Jiao, and BJJ.
Cung Le most people probably know. Solid MMA record in a US org', undefeated in Sanshou - he's out there reppin' kung fu. 'Nough said.
I'm not trying to say kung fu trumps Thai boxing, I'm just hoping I can point out that this argument isn't as one sided as many of the Muay Thai boys are trying to make it out to be.