When you do check the code, look at code history to see when it was tripped - first and last. If it was before the collision, you have irrefutable evidence (even if it was after, really). The only way this data would prove the claim is if it was tripped when the collision occurred. Regardless, there is retrievable data in the PCM which your coworkers insurance company should demand access to in order to prove or disprove the claim.

David Schutz
Technician/Manager
Empire Builder Auto, LLC
Saint Paul, Minnesota, USA