All I submitted was a letter from my doctor in Bkk that stated I am a patient of hers and that hospital. It was on official hospital letterhead and signed by the doctor. Was approved no problem with no additional documents requested.
The only thing I submitted was a letter from my doctor in Bangkok stating I was a patient of hers and of that hospital. It had my passport number and hospital ID number in it. It was on official hospital letterhead and signed by the doctor.
Mine wasn't denial but was medical. I didn't show any appointments, I just got a letter from my doctor saying I was a patient of hers and the hospital. It was on official hospital letterhead and signed by the doctor.