Hiding in a country as corrupt as Mexico with a million dollar bounty on his head might be tougher than he expects.
He'll never be the "head" of a major corporation.
No more so than anyone working for any of the cartels, who also have bounties on them.
What Dorner knows is of value to the cartels. If he really wants to make war on LAPD, joining up with a cartel is a good way to do this and make some serious money at the same time.