1998 Cadillac Deville Fuel Pump dead

Hello, I run an auto detail business, recently we had a customers vehicle in that seemed to be running fine when it came in. It did have service engine lights on, however was starting fine. When we were finished with the detail the vehicle started after many cranks of the starter, and we pulled the vehicle outside. After trying to start it again, it just started turning over and over, but would not turn on. We jump started it and it started and he drove home, thinking it was over and done with. He calls me today and says the car won't start now and that his mechanic said the fuel pump is fried. He said they "hot wired it" to start but it keeps blowing the fuse now. He is now trying to blame the damage on us saying we did something to cause it to break because this never happened before. We did not clean the engine on this vehicle, just shampooed the carpets and buffed the outside. Is there any possible way to have done any damage (electrical or otherwise, wiring under the carpets etc?) To have caused this. Thank you for the help