makes absolutely no sense. How can any Bank tell you that they can't accept fund transfers into the bank? This is something done billions of times per day around the world.
Any Photo shop, passport Photo shop will print one out and laminate. The evisa website requests that you print out your approved Visa, do it or Santa strikes you off his list
I'd go for Hanoi, it's probably more predictable. Having the ticket out of Thailand most certainly in your favor if the DTV isn't approved. What is too many visits, and in what timeline? If denied you could also use a fast track service returning from Vietnam to Thailand.
Out of the approximately 100,000 or so DTV applications I know of, there was only one approval for a language school. Keeping that in mind the whole story sounds like horse feathers. The Thai police aren't running around saying show me your tax papers. It's also four months till tax filing deadline. Furthermore it doesn't matter what kind of Visa you're on after the 180 days, making you a tax resident, except for LTR. I saw a retiree getting pulled out of his wheelchair and having to show his pittance pension papers.