“[...] suggest the early human relatives ate more meat than do carnivores [...]”
Stopped reading right there. That statement makes no sense at at all. Where did editing disappear to?
Carnivores eat all of an animal including the stomach and intestinal contents. I don’t know if Neanderthals did that. I remember a story of an Indian zoo. The local Hindus were very proud of their lion and fed it the best meat. The couldn’t understand why it got unhealthy. They were advised to give it the whole animal to eat, and it soon became healthy again. Stomachs often would contain greens and seeds from deer, antilope, mice, etc.