I'm assuming that the one that got him killed is the one he saw. But if he's dead, then we don't know which choice is the right one, and yada yada, each branching path creates an infinite number of new futures, and-

[And Tony's paralyzed with indecision and kind of on the verge of a panic attack here, okay? He doesn't understand why he's alive and Strange isn't here to do things the right way.]