Has anyone suggested that maybe this whole "uncontacted" tribe thing might no longer be a viable situation?
I mean, I get why they do it, but I think if the tribe in question is contacting outsiders with bows and arrows, they might just have to suck it up and join the modern world.
Rig up a bunch of darts with a heavy duty cocktail of vaccines, shoot up the tribes people, leave 'em to there own devices for a week or so, and viola! Time to invade with Coca Cola, candy and TV.