I hate surprises....

[GSPI]

Based on the tear and the seat stud re-welding, I'd say to look for front end suspension damage too, possibly on the passenger side of the car. The car must have had a severe cross body torsional flex occur (I have some other big words too but it got twisted is basically what looks to have happened). If it was a hard enough hit you should see some buckling in the framework metal on the front end possibly from running something over or going off road. These cars do not have a completely rigid chassis (that's why those aftermarket frame rail connectors and the shock tower connectors are available) and the flex can occur if there is a severe enough bump on one of the front wheels at speed causing the twisting motion to occur and overloading the floor pan and causing that rip which also probably tore the seat bolt stud out too.