Maybe a tip: Friend of mine did not have a bank account but could put 800k฿ on some kind of account, in his name, at the Bangkok bank. It's a yellow/orange bankbook so think it's some kind of fixed deposit account 🤷♂️. Did not pay attention what 'the book said'. He did not have a regular account with debit card, app etc. He got his year extension (retirement) with that. This was Korat imm.
Last March you also wanted to take someone to court I read. How that worked out ? I know 'to sue' is a nice verb in the US, but this is Thailand. Good luck with it.