So the woman is married but the husband is not being the sponsor his mom is. Sounds kinda fishy to an interviewer right from the start. That’s probably the problem right there. They could possibly be thinking this is a shame marriage and the wife is coming to be the sponsors paid care giver. Working for room and board is considered earned income. And is a violation of the visa.
Not knowing the particulars about mom’s income. But if she is on Social security and the income is too low that could be a red flag. Many on social security don’t have enough income that they need to file taxes.
2.4% is a bit less than 20,000 baht per year. If that’s going to derail your retirement then you should probably consider a different option. You could transfer the cash around to better paying accounts then return that as needed for immigration checks.
go visit one stop visa on Soi 6 Pattaya. They will hook you up with a bank account at the Bank of Bangkok. Can get you a drivers license with a motorcycle endorsement if you need it also.
It says the 20th. It won’t arrive until then. They want to make a little interest on your money. They are a business trying to make money on your money.
Never offer up information to any government official anywhere unless asked. Keep your mouth closed. Most people that get into problems is because they blab unnecessarily. If you do get asked just answer truthfully and to the point.
Thai immigration may accept a one way ticket. But not all airport ticket agents are experts in Thai visa regulations. They get told that passengers need an onward ticket and they gonna enforce that.