Jack wasn't in Mexico, he was in Mojave CA, which I guess is not too far from LA. When he calls the kid's mother, she was enroute to LA, but wasn't there yet. The airport to which he directed her was the Ontario airport, about 30 miles East of LA.
Mohave is in the high desert of Southern California -- on the road out of the valley toward Mammoth..... Edwards AFBase, etc.., also one of the cuts across from Barstow to Bakersfield cuts through Mohave...