I chose
Datu.
For the longest time, I would swear by
Kelly. She makes the most sense overall to me. But two things changed my mind: I relistened to The War chapter, and the person who first defends
the Tower as a weaponless resident is Kelly. She is the first person to throw a couch over the balcony. She's trying to defend their home. I also keyed on
Jim Gleason's reasons why Datu survived (thematically) in the stadium as stated on the
We're Not Dead podcast. Datu has a never say die attitude and it serves him well. He survives because he has faith that he will.
Samantha's fatalist approach to her situation lends to her destruction.
Since the encounter at the Stadium, Datu has adopted the fatalist stance (and become an insufferable annoyance). He's also got severe survivors guilt. When he returned to the Tower, he was crushed and couldn't care less. And he's the only one we never heard at the party.
Can't you just see him talking to
the Mallers on the radio, depressed and choking up wanting them to come in and end his misery? He can hear the merriment of the party and it just grinds on his last nerve. Why can't he and Samantha be up there having fun? Then he gets more pissed that they aren't coming in to kill him fast enough so he fires off the first rounds to make them come faster.
So call me/it crazy, but I call Datu trying commit suicide by Maller.