If she graduated university recently, she can appeal that she needs English proficiency to get a good job in Thai.
Usually, If student graduate recently, it's easy to get a visa. Try one more time and if she got denied again, she can come with tourist visa and change her status here.
However once she change of her visa status in the U.S. she can't go back and forth. She is gonna be stuck in the States until she complete her school.