I lost a turbo with 21k miles, same tunes. Dealer not only said too bad, but tried to sell me another engine claiming "likely catastrophic failure" I can't say what they looked at but they didn't remove a damn thing. My advice to you would be to do the same thing I did and upgrade to the 15 retro kit. Even if they cover it, I'd be leary of trying another crap turbo failing down the road. And if they do deny it, they'll charge you more for the same crap stock turbo than a 15 retro kit costs. I spent $2900 on a retro kit and about 5 hours in the driveway. Hell of a lot cheaper than $18,015.00 plus tax they tried to get me for. I send oil samples every change and oil confirmed no wear metals whatsoever. I'm about to send a short run 1k mile change just to be sure but truck runs way better than before. If you want to stay tuned and deleted, I wouldn't put another stock turbo on there or you may be doing this again down the road. No warning with my turbo either, she just went. Good luck whichever route you go.
Keith