Cranks but will not start

I checked the crank shaft sensor and is good. It keeps turning but wont start. Also the starter when I try to start the truck it keeps starting until I close the ignition switch.

I already check starter and it good. Also check the wires and they are okay.

Good evening, I replaced the crank sensor and I took the starter to AutoZone to check it and it is good.

Had Timing chains replaced at 20,000 and again at 106,000. Started having random misfires at 110,000, had a friend (ASE Certified) check why, he found that the front cat was clogged. I replaced but during the replacement found a chunk of catalyst stuck in front of 3rd cat. Repair completed.
Within 200 miles as I was driving- everything seemed normal, came to a stop at an intersection when I tried to accelerate I had no power. Made it maybe 100 yards and it died.
Hooked up scanner - P0343 and P0367. I swapped cam sensor to see if problem would move from bank 1 to bank 2. It did not. GM garage said it was highly unlikely that this is related to timing chain- that it is most likely a short in the harness (or to ground). May I have your opinion and maybe some trouble shooting advice (maybe a schematic or pin-out at the ECM?)

Thanks,
John