The end is a dream he constructs for himself. He said he couldn't go back to America, and if they fail he would get arrested at immigation if the plan fails. When he does wake up on the plane and after the phonecall is made, at the end when meets his kids, the Michael Caine character is present. But he goes to see the Micheal Caine character earlier in the movie to recruit a new hot female 'architect' - how could he make that meeting if he couldn't travel to america?
If he could freely travel back to the states to see Michael Caine earlier, then whatever method he used to achieve that he could have planned to use off the plane.
The logical conclusion is also therefore that the entire plot is a dream, and the plot is therefore almost entirely pointless.