Korat Immigration sometimes ask for a hand drawn map from your house to the Immigration office. Easy if you live nearby not so easy if you live some distance away. They will not accept a Google map!
I tried to pay at Sizzler in the Mall and they actually had the card reader and a pad to enter the 6 digit pin. It came up with a transaction denied message. Now I just use it as an ATM card.
I hammered them pretty hard but they just don't have Visa cards to issue. I have banked at this branch for 15 years and the best advice they could give me was to open an account at a different bank.
I tried at my small branch in Non Thai and the branch at the Mall and both said "can't do". Will try at their regional head office on Chumpon Road when I'm next in town.
I would avoid Bangkok Bank as they no longer issue Visa debit cards. Instead they issue Union Pay cards which are of no use whatsoever other than as an ATM card at Bangkok Bank ATMs.
I think that they only give a 90 day single entry at Savannakhet based on Thai child. You would then need to go to your local Immi office and extend that for a year with 400k THB in the bank or 40k per month income proved with a letter from your embassy.