quite possibly, no issues her. But the O visa and retirement extension will cost her in and around 40,000 baht.. ..15 months total......thereafter, 14 to 16,000 yearly for renewal. Jus' saying. .... Peace of mind for sure and seamless.
Google and official Thai websites explaining the matter clearly are a great invention. First you do your initial research and the hard work and then you come to a forum to clear up any unclear details. That's how it works