Are you saying the only recourse is to cross the border illegally?
For a Mexican that is pretty much true
How Do I Become a Lawful Permanent Resident While in the United States?
The US has a limit on Immigration of I belive 370,000 a year and that is amoung all countries
Mexico has a share of that number which is allocated to people who have family in the US first
I knew a legal resident who tried to sponser her sister back when Congress did the 1986 immigration reform act and was told that the wait was 35 years.
So this guy has no shot at all