@Bruce ********
Even if she did get a visa (it’s not impossible) for Mexico. And you tried to go through land border. They would turn her away. My Filipino wife was a permanent resident of Canada. We lived in Winnipeg. I was driving to Windsor Ontario. I wanted to go through Sault Ste. Marie Michigan because it saves 12 hours of driving. U.S. immigration wouldn’t let us drive through. It’s a 6 hour drive. The female immigration officer was stamping her refusal for entry papers like she caught Al Capone. Coming back I went through Detroit tunnel. I had a Customs Officer. I already knew my plate was in their system. I pulled up. Flashed my badge. (I worked for CBSA) First question. “All Canadian?” I no sir my wife is a permanent resident we’re just driving through cuz it’s only 6 hours. He nodded his head, he understood. Then cocked his head to go through. “Thank you very much!” He had common sense.
I looked into Mexico. Make sure she has money in bank. A criminal record check. A return flight and hotel booking. Ties to bring her back to Thailand. She could probably get one.