With the risk of sounding like downplaying it, I think the crucial part here is the potential range of the helicopter, which is fairly limited with the information given (start location, time etc.), and the fact they can walk in from somewhere flat enough to land the helicopter.

The geological part is nice but not necessary (you just need to be able to tell the colors of rocks).

I don't think it would have happened without the helicopter flight path....utah is a big place, even with a lot of geological clues.

this type of knowledge is quite expected from certain analysts in certain agencies [this comment will self-destruct in 5 minutes]