This is an interesting part of your article, because I've done this too. When I revisited Deliverance, I was convinced they all died, based on memories of my first viewing (Jon Voight, Burt Reynolds, and Ned Beatty, as well as Ronny Cox). But of course, they don't. My memory of the film only went up to them attempting to escape along the river, and in my mind, the hillbillies got them all. I even had an eerie "final shot" of the river in my mind, which did exist, but was part of a nightmare Jon Voight has in the final scene (after he's safely back with his wife).

Obviously, I must have been too young to watch Deliverance the first time I saw it, as it so disturbed me I blacked out the entire third act. But yes, the memory really can cheat at times.