In the first week extensions started, when they were vague on rules I admit.. They told me that a non Thai account would be accepted, and to prepare all the Docs I initially applied with..
But that was early on and I suspect theres a lot of very edge case 'workers' so the DTV is likely to remain a hit and miss process due to these reasons IMO.
Fairly standard.. They want to see the role can be done remote (letter from the company on Letterhead) and proof you work for the company (payroll report, payslip, employment contract etc).
Maybe include a tax return (I uploaded an annual statement)
Carl Turner youtube channel.. Interview with Senior Revenue inspector and also the Panel Q&A with the same guy and Ex snr revenue who is now a professor of the subject teaching future staff.