I think that is a possibility.
Native Americas believe they are the original people.
Perhaps they are right, and the Red Haired Mummies were making their way west from their homeland in the New World (after having moved there as ancient human stock over 100,000 years ago). Perhaps the Joman/Ainu came from the New World, then went on to populate Australia and the Pacific Islands.
There have not been any skeletons of American Indians/Native Americans older than 6,000 years old ever found in the Americas. Skeletons older than 6,000 years are other people more akin to the Kennewick Man variety.
There is one skeleton found named, 'Stick Man,' that does not 'fit' anywhere with known living humans, from James Chatters in his book about Kennewick Man, Ancient Encounters.