I think you might be right. Focusing a bit to much on the positioning might be of if they actually filmed it afterwards. However the two corner people wouldn’t work out due to the lighting and even if positioning would be a bit off, it wouldn’t be that far of. So it does rule out these two.
Before reading your comments I thought that it actually was gonna be Abraham. He is a champ and the group he came with when first introduced still got all it’s members alive. Also killing Maggie would mean last person from her initial group dies.
However another point in favor of your theory is something I read that got stuck in my mind: “It can only be one baby in the show”. *comic spoiler going forward* While her baby does make it in the comic which made me believe that she’d survive at first, Judith does not, so there is only one baby in the comic as well. This pointed towards her baby not making it, so her not making it makes sense.
Also I understand it Carol doesn’t make it in the comic, so her taking over the role of Maggie would fit into that as well I suppose. But then again, during season 6 Maggie did get more of a delegate role towards Hillstop like when Rick told her “You should be doing this”.
Only time will tell. But I suppose it does kinda makes sense and for sure would stir things up.