I doubt these audiobooks are mistranslated in any meaningful way: these are actual native speakers making these audiobooks — I say "small and endangered languages", but I should be clear to say that these are languages with tens of thousands or even 100K+ L1 speakers — and they're apparently working off of old Bible translations from before the languages in question were endangered.
I'm assuming you're thinking of the absolute scourge of AI slop Indigenous language dictionaries and learning materials that are genuinely hampering efforts to revitalize these languages, but Today's Native isn't that, it is as far as I can tell just straight up Indigenous Christian boomers making content for other Indigenous Christian boomers.