93' chevy lumina

I know that the computer for this car is under the hood.. I was hoping that someone could tell me if the computer could cause a fire in the dash? we had a major fire and the car is toast basically, we were told that the computer caused it.. I am trying find out if we are basically getting lied to about it. someone did some work in the dash just a couple of days before the fire.. I don't know if he is trying to weezle out of being liable...any comments would be appreciated..