Mike, the second part of your comment didn't come through because of a permission problem. Am I looking at the wrong document when you say Para 77 which seems to be about penalties for false claims. If so I think we are talking about two different things. I am looking for a certificate, possibly called RO22 according to Google, which shows that a company already pays Thai tax and is resident in Thailand. (This is for a company or as Google says an 'entity', not an individual.)
For those selling through some of the large US online companies you already probably know about EIN numbers from the IRS and Thai/US tax treaty. Google are now asking for this new certificate. According to my local revenue department office this form has only been issued since the beginning of the year and has to be obtained from the revenue department's regional head office which in my company's case will be at Huay Kwang. I suspect if Google are asking for it, it won't be long before Amazon, Apple and the others will also want it. The difference it could make is between 5% and 30% of IRS withholding tax.
Now it seems that there are similar forms for individuals as well as companies, but they will need the individuals to be paying Thai taxes. Hope this is a bit clearer. The accountants that handle our company are now inquiring about it with the Revenue Department. I will try and post more information as I find out. I noticed the RD's website had slightly changed or update the required documents this morning. Here's a link.
https://www.rd.go.th/22740.html