US work permit process
I entered the US way back when on the H2-B and have regrets over paying the lawyer for the help ($2000) for visa that only lasted 12 mos.
The best route is probably the H1 route or the Permanent Residence based on an application proving that he is "not replaceable by an american."
That process was called the "Dept of Labor" certification. But the best route will be the academic route with a work / study where the yanks are short handed - i.e. science. Any field that requires science, math, or computers might make it easier due to shortage of skilled labor in that area.
I am dating myself however, as I went through all this in 1995. Canada is a breeze and highly recommended plan B for him if he gives up on USA stuff.