Diesel Bombers - Broken Crank?

About 2 weeks ago on the way to work the truck started bucking violently and died. Pulled codes and got p0366 crank sensor. Took it to a mechanic I know and he replaced crank sensor. It still throws the code after clearing it when cranking. We are getting power and signal from both the crank and cam sensor. The reluctor wheel is tight. The truck is building fuel and oil pressure while cranking. The guy I took it to is not knowledgeable on the Duramax so he didn’t want to start taking a lot apart. Anybody have any ideas and does anyone know of a reputable diesel mechanic/ rebuilder near St Louis.