Try asking on the Destination Thailand Visa (DTV) group. If you use the search function there’s probably someone who’s applied from the same Thai consulate
In the Muay Thai scene it’s usually not recommended to get an ED visa through a MT gym.
You have to pay for a years classes upfront and gyms often change or are not as good as they appear to be on social media. You don’t want to end up stuck at a rubbish gym for a year.
What most people do is get a ED visa for Thai language school and take 2-3 classes per week, but still enjoy the freedom to go to which ever MT gym they want.
This was before the DTV. Now everyone is applying for the DTV instead of ED.. unless of course they don’t have the necessary funds.