I was and still am scratching my head on who it was and I didn't see any one snipe said person, so...still alive is my guess. I haven't gone back to watch the scene, but I remember thinking it was a chick. And no, it can't be Andrea, because that would be F*CKED UP to do them like that. But then again, she made a BIG show of wanting to know where the Governor was at and maybe releasing the Walkers would be her way of ending the firefight temporarily and get One-Eye Dildo Man back into town without any further bloodshed.