For some reason, I don't think it was Carol. I think she's covering for those girls. There was someone lurking ominously in the cut as Carol was hugging that one girl, almost as if he/she was waiting for their opportunity. And that chick on Talking Dead just said "IF she did kill those people"
Scratch this. Looking at it a second time that "lurking ominously" was actually an angle from inside the cell block where they were keeping the sick, so it couldnt have been someone plotting. I still dont trust them girls tho. Two of em couldve dragged a body and Carol was saying one of em was weak cause she couldn't do what needed to be done, almost goading her to be on some boss shyt