There’s a New Theory About Native Americans’ Origins

Wow. Check this. Gotta rant. 
Apparently the sampling was done with volunteer Native Americans, Polynesians, and Siberians - resulting in an inevitable conclusion: all Native Americans came during the one "wave" of migration.
I think somebody is naive and I hope it is not me. I am suspicious of their sample sizes, and am suspicious of how they sampled tribal diversity and did they "cherry-pick" the genome to get the desired result? And, by the way, it is not a "new" theory, it is the same old theory.