I am watching a Christian show with a very accomplished paleontologist as the guest. He is saying that the Neanderthal is just another people group that existed. That make sense to me.
One thing he points out is that the Neanderthal was shorter but stockier than the average humans of today. Since they were stockier their skull and space for brain was bigger. This is the opposite logic for evolution, because if evolution was true then the brain of a Neanderthal should be smaller. The brain would increase in size gradually in evolution from monkey to human. If they were another people group then them having a bigger sized brain does not contradict any scientific logic there.