@Andrew *******
@Pete ******
is completely right that your story about DTV not being tax resident is complete nonsense, especially because the argument that the money is not traceable, but I can believe you when you say that revenue department told you so.
I heard a lot of conflicting stories about people at different tax offices.
One of the things that you always have to take into account in Thailand is that Thai employees do not like to do anything they are not used to do, which might result in incorrect handling of situations.
A foreigner that has to file tax for some is already unusual, so just telling you don't need to do so is the most simple solution for them.
Asking their superior makes them look less intelligent, so that is also not the best option.