That’s very interesting. It seems there is evidence (and always has been) for a multi-factorial answer to the question of American Indian origins. And your experience conforms to my reading, that it’s not the American Indians who reject this - it’s their vocal, mostly white, ‘advocates’, who insist on the single origin Bering Strait story.
And it isn't only the insistence that makes me suspicious, it is the dogmatic rejection of anything else which even hints of slight deviation from their theory.
The grizzled old Sioux professor which I studied under first begin teaching back in the 1930s. He had lots of friends among students and professors in other departments, but none that he could name in the field of anthropology or the new field of Native American studies which was just getting started when I met him in the mid-1970s.
He never would have been hired had he started out then, even though political correctness was just beginning to take root.
It makes you wonder what the "profession" is trying to hide when they have to be so strictly dogmatic. Sort of like the global warming industrial complex . . .