No, he does not have those sorts of regrets.
See this interview 10 years after the tragedy:
John was told to identify himself. When he did, the second killer recognized him. They had worked together on stage crew for theater productions.“Are you going to kill me?” John asked.“No, dude. Just run. Just get out of here.” Savage was spared in a room where 10 others died, though he saw none of it. He heard gunfire, snippets of chilling monologue from the killers.He remembers thinking that if he were going to die, he wanted it to end quickly. When the gunman told him to go, he did not wonder why.That would come later.“I’ve tried to go over every word of every conversation with him, trying to figure out what I said or did that made him want to let me go,” says John, now 27. “But just that I was nice to him is all I can think of.”
In the time immediately following the tragedy, John struggled for perspective: Was it like being a soldier in combat? A bystander to a bank robbery? He replayed the scene with alternate endings, like the “action-hero scenario” in which, using only his hands, he prevents further violence. Reality reminds him that wasn’t possible.“I was talking to one guy, and he said, ‘Why didn’t anybody take them out?’ ” John recalls. “It doesn’t work like that. You can’t just punch a guy with guns.” He got counseling after the tragedy and found he had “not as many issues as you’d think.” But he did have some dreams in which the killers survived.“They were brought to trial, and I was a witness,” he says. “It wasn’t a nightmare. Just a fragment, me sitting on the witness stand.” The dream ended without resolution. John understands survivor’s guilt, but it was never part of his personal reckoning. He found solace in his Mormon faith and the belief that everyone’s fate that day was in God’s hands. [Source]