Have you checked out the Rosetta Stone endangered language program? I don’t know what criteria they have for partnering with language groups. It’s not part of their normal programs. It’s a partnership with the native speakers who have control over it. I mentioned the Navajo language in another thread, and they are one of the Rosetta Stone partners.
All of their current languages are native languages in the Americas. Although at least one may be spoken in the far northeast of Asia. At least one the native languages in the far north of North American ( plus Greenland ) is also spoken in the far NE of Russia. This is due to back migration during the Bearing Land Bridge migration. The US and Russia are even working on a cultural partnership to tie the cultures and languages together.
What I find sad is how political machinations have affected cultures and languages. Like here in the Americas, the US and Canada drew lines of demarcation. In some cases that line divided native cultures and languages, effectively splitting them and making the language more difficult to maintain. If you’ve seen the movie Dances With Wolves, I think they speak true Lakota in the movie. Lakota, Dakota (like the US states) and Nakota are all dialects of the same language. The original speakers spanned what is now the US and Canada. There are only a couple thousand Lakota speakers, and only a couple hundred Dakota speakers. It doesn’t help that their people were geographically split by political boundaries.
I image the same thing has happened around the world where political lines divided people. Of course what’s even worse is when the powers that be systematically suppressed a native languages.