I actually went to thailand first on a visa exemption. I got an MRI and saw multiple doctors at 2 hospitals and got evaluations. I went to both Samitivej in BKK and CM Ram in Chiang Mai.
They were able to send me all the documents via email.
I did it for medical care they ask for a 6 month treatment plan, diagnosis , and note from thai hospital assuring that you are under their care/letter of participation