dd13 cranks but no start

hey everybody, seems like im always having the weirdest issues. 2017 cascadia dd13, unit came in and injector line pass through seals were replaced with new injector lines. unit would not start after, just cranks and cranks, primes fine, and backfires thru intake on starting fluid for some reason. looking at the instrumentation during crank, fuel compensation pressure is at 13 psi, lppo pressure is at 52 psi, engine fuel delivery pressure is at 76, rail pressure hits 215 bar and steadily comes back down after crank. cylinder fuel rate hits 75 mg/st, engine start and firing allowed is true and mcm receives a start signal. rail pressure relief valve replaced. two stage valve replaced on pump. capped off return to see if it'll start and nothing. no active codes at all. At a loss any help appreciated. one thing it does do is the egr valve clicks like its trying to push the rod even though the rod can be moved by hand freely.