No. It should be from a foreign source. But i dont know if you cant transfer money to his account in his home country. he can then transfer it to his account in Thailand from that account in his home country. Just a possibility.
some officers may like to see the monthly deposit on same date each month and marked on the statement as a pension. They like regularity from the same source.
You need a visa to enter the border country at ranong I think Burma I forget now. but i did a visa run to Satun a month ago rather than ranong because of need for visa at this crossing at ranong. No visa needed to enter Malaysia at satun. I used kvb visa run out of phuket. Great day no issues.