We find that Kennewick Man is closer to modern Native Americans than to any other population worldwide.The paper is marred by strained, politically-motivated attempts to tie Kennewick Man specifically to "the Confederated Tribes of the Colville Reservation (Colville), one of the five tribes claiming Kennewick Man". So those interested in aboriginal American population structure are probably better off ignoring much of the authors's narrative and looking directly at the data.
The ancestry and affiliations of Kennewick Man
Kennewick Man ancient DNA. The paper is openly accessible. Results pretty much as I expected.