These newer complex diesel scare me for sure. I know statistically things like this are rare but they seem more common than before all the high-tech emission stuff.
The great thing about diesels use to be they towed quieter/smoother and they'd run forever. While the engines well may run forever, something else that's really expensive will probably fail before the engine.
And this isn't a brand specific thing at all. It seems any/all brands could have really expensive problems. From reading various message boards and hearing experiences like the OP's I personally have zero interest in owning a modern diesel that is not under some type of warranty. Maybe I'm "throwing the baby out with the bath water" as the saying goes but it just seems like there are too many unknowns and new systems with modern diesel engines.