If they did not use fire, that would be excellent evidence that they are a different species.
Humans require cooking to render food sufficiently digestible. There are no examples of human societies not using cooking and when modern humans try to survive on raw food by “hunting and gathering” in a supermarket they have difficulty maintaining weight and women become infertile.
I have always been worried about ‘facial approximation’ based on limited fossils. It seems like too many assumptions are being built onto assumptions. Which leads me to wonder why they bother to use it at all. Once it is sitting in front of them, it’s going to inform all sorts of their future assumptions either consciously or unconsciously.
Innuit used to eat a diet of largely uncooked meat. There was no fuel for cooking, other than the food they need to eat during the winter months (i.e. whale/seal blubber), so they evolved to eat raw meat and lots of it, with very little plant material or cooked meat.
Not true. The Sentinelese people supposedly do not use fire to cook. http://en.wikipedia.org/wiki/Sentinelese_people On other sources I’ve read, they’ve been observed to have a fire, and manipulate fire, but only when the off chance occurs that it was created from natural causes. They have not been observed to have the knowledge of how to create their own fire.
Also, the use of fire is not an indicator of speciation. Hypothetically, if indeed Homo sapiens need fire, the very first “human” to live required it to survive, but their nearly identical parent did not.