@Michael ******
I am not familiar with DTV and Muay Thai. If your DTV is based on that, does it have to be a gym where you will be actually training or any gym in Thai can accept you?
You said you are in Kanchanaburi (been there, River Kwai), it is a fair stretch hours and hours, even flights to Chiang Mai or Phuket that other replies suggested.
Just tell us here, for the benefit of other members of the group.
50m from my home in Bangkok, there is a Muay Thai gym, it did not exist before the DTV was introduced.