Thai M.ed Or Grad Diploma In Ed.

I'm currently in the transition of changing careers and seriously considering the education field. My wife is Thai and has her M.Ed from a university in the USA. She plans to open her own language school in Thailand. I have a BA (USA) in one of the social sciences and M.Sc (Europe) in int'l development. My credentials are insufficient to land me in one of the better schools, so would it be worthwile to get a grad diploma in education from one of the international programs at a Thai university? Alternatively, would it be of any benefit to get a M.Ed from one of the international programs? Time restraints will prevent me from getting it in the US. I plan to teach exclusively in Thailand or perhaps a stint in another Asian country, so would the M.Ed or post grad diploma be sufficient for Asia, and also recognized by a good EP or middle of the road international school?

I would prefer to teach social science but would not complain about English. I have some, but limited, experience teaching. While in grad school I taught English while doing my field work in another SEA country. Should I even bother with this or just apply to a university instead? I do have a sincere desire to teach but I would also like to make sure that I would get a return on my investment. What are your thoughts?