Hello all, I have a 2018 Tahoe police package with intermittent start failure. We just can’t seem to diagnose the issue. We have replaced both batteries, starter, alternator, power distribution block for the auxiliary battery along with the wiring harness to same. All fuses and relays related to the starter and ignition have been checked as well. Two separate keys were used to try and start the truck in the video posted. The only thing left to replace would be the ignition switch? Possibly? Any insight on this would be super appreciated as this is an important vehicle used in our EMS fleet.