As long as you have the supplemental, there should not be an income-related problem in ultimately getting the application approved. Yes, he can apply for a visitor visa or a student visa. However, in order to satisfy the consulate of his intention to return home at the end of the program, he will need to submit sufficient documentation to show ties to his home country. He should include such things as evidence of his family's ties to their community, assets there, possibly a job to return home to. If he can't do this, he probably will not get the B visa.
Many different attorneys give different, sometimes incorrect information.
Look for a member of the American Immigration Lawyers Association and then check with your Better Business Bureau or the State Bar association to see if they have complaints filed against them. You can also ask potential lawyers for references but not everyone will be cooperative with giving them out. My daughter has an H-1B visa and has found a new employer. They transferred the H-1B to this new company. My H-1B expires in June 30, 2001.