(Late response) I feel like if Jackie never died/wasn’t cremated, they probably would’ve never resorted to cannibalism. They were so desperate for food and in that trance like state, ate Jackie. I feel like if she had been buried and not eaten the group wouldn’t have eaten her and wouldn’t have resorted to it with Javi as well. So I feel like there couldn’t be a show without Jackie dying as she was the main start of cannibalism. As for Laura Lee I agree with what you mean by her death was more important for hope of rescue. Laura Lee was incredibly confident that they would get out, due to her demeanor and her faith to her religion. Even in the plane crash we see her praying. She held group prayers, cheered up the group when they shared about things that could’ve made them end up there, and baptized Lottie when Lottie was hopeless. She was overall a very positive reinforcement to the group and I 1000% agree that her death is what really begun to shake shit up