Yep, that's okay. I am, like the op's father, also from a country from where they still accept the income statement from our embassy. Happy with that so (in my case, retirement) no 800k฿ blocked (or 12 times 65k฿ as international transfer. We're not even allowed to do that as income proof)
Not quite. Father in law is from Germany so no 12 months 40k฿. It's an income statement from his embassy (Affidavit) or the 400k฿ or the combination method (Total of 400k฿ income and banked money)
. If they see the sticker in the passport they almost certainly use that. But you can ask the imm. officer. Should you have an E-visa (printed .pdf) your chances are a bit better, but still not sure they do that. Think they can see in their system you have a tourist visa. Not sure about that.