Sacrifices Question

Have we seen evidence left over from the sacrificed victims (as in their blood or body parts) to confirm they are actually killed? Obviously the stakes are high, and people die in gruesome ways on WB. But in trying to piece together evidence of potential opposing forces at play, what if the people sacrificed don't die, but are taken/kept by the entity? It could set up an interesting dynamic if the entity and the evil island are separate/enemies. Farfetched, yea. Possible, maybe! The reason I want this is because I'm hoping that Lauren was fed to the entity, and she could possibly be brought back one day after the island curse is broken.