The white smoke is normal out the EGR... I literally don’t hear a misfire. A misfire is a lot different than what you’re experiencing. I don’t think it’s the turbo. You would smell oil out the exhaust and it could be either white or blue. Personally if every o-ring is replaced, and every line, it could be a dirty or clogged injector.

What I’d do is diesel purge it. Depending on the mileage too and the quality of the fuel that was put in it in the past, it could need new nozzles and for them to be re-shimmed.