Update: Autoguard, the extended warranty company, has stepped up and is going to pay $7,500 of the almost $14,000 bill. I am very grateful for this. The truck was out of warranty by only 883 miles, but out of warranty none the less and they didn't have to pay anything. Additionally,
@RamCares reached out and has opened a case so I'm hoping they will come through with some help as well. As far as a cause, I have no idea. Generally speaking I keep an eye on the dash lights and nothing ever came on. It wasn't running hot, and the dealer hasn't mentioned anything about the oil being low, let alone gone. (I would think this would be one of the first things they checked?) It just shut down completely out of the blue. I'll keep updating and thanks for all the input.