antij0sh

I have a dealer service tech claiming that when he tried to update my PCM (for a service campaign) he bricked the ECU, and he's blaming it on some third party software on the ECU, however he cannot provide any evidence. His claim is that "The only thing that would make that happen is aftermarket software". Now I don't believe the car was tuned in anyway. But his claim doesn't even seem logical to me.

Would having a tune make a factory PCM upgrade destroy me ECU permenently ?