All good suggestions, and although it sounds like a newer truck, make sure there's no corrosion on the terminals and the grounds are tight as well.

A bad connection will act fine with little current being drawn but will not do anything once you put a load on it like a starter has. But to me it really sounds like something related to safety/security of the truck..like the coded key or a bypass relay somewhere is tripped. I really imagine a dealer is going to be your best bet, unfortunately.