I am having a similar problem with a no crank "starter interlock truck disabled message on a s50ft (f187v, 2.4 GM). I welcome any advice...
The service call started with an error about the impact sensor, cleared that and disabled the impact sensor.
starter cranks and truck runs if starter is jumpered to engage the starter solenoid. relays are tested on known good truck, and can engage starter from starter solenoid connection in pdc.