Are you referring to the actual gym Phuket Muay Thai? I've trained there and found them very reputable. Also not sure about the language barrier as the owner is American. I wonder if there just some misunderstanding perhaps?
I am not familiar with this embassy - but the embassy I applied from had stated 15 days and it took 18 working days. I think overall the process may just be taking a bit longer. But it'll be worth it 😅
I was given the date and time (KL embassy) - I got the email around 6pm for an appointment the next morning. It's pretty short notice- maybe to ensure you really are in-country....