No, what makes no sense about Carly, is that she actually knows she was a Dark Signer. If She cannot remember her time as one, how the hell does she remember that she WAS one? You dont know youve become a Dark Signer until you actually die. In her case, when the hummingbird appeared to her. She became a dark Signer, and automatically knew it. Well... no. That was her Dark Signer persona. the "real" Carly that came to after battling Divine didnt quite know she was a Dark Signer until Misty came and picked her up. either way, she didnt learn she became one UNTIL after she died and was reborn. So she really shouldnt remember she even was one.
also, the thing on the souls, I can see as Rudger and Rex sacrificing themselves to revive the others... Though they did not exactly explain why Rex and Rudger weren't revived as well. They just sort of "walked into the light" with out an explanation.