1) A cut jawbone and a necklace of teeth is not strong evidence that the Neanderthal was eaten.
2) Early French Dahlmer, one cannibal does not indict all early French as canibals.
How the hell do you get “cannibal”.....out of a necklace???
Scouring the meat off a bone with an edge leaves characteristic marks.
But maybe he just wanted a cool Neanderthal jaw; either way the flesh was stripped off the jaw and the teeth collected to make a necklace.
Finding Neanderthal remains in human feces would definitely settle the matter of if humans ever ate neanderthals. But given how long neanderthals and humans lived with each other, and given how common cannibalism has been in human society; I wouldn't be willing to bet that such a thing NEVER happened, although I am sure early humans could find easier prey to make a meal of than a Neanderthal.