Sorry to hear about your accident.

But glad that you're OK!
I'd get the bumper relaced if I were you.
You really only need one estimate to give to the insurance company. The law says that the insurance companies can't tell you where to get repairs done or that you need to get more than one estimate. One estimate is sufficient. So, if you get an estimate for a new bumper that is what you give to her insurance company.
Just went through the same thing with my daughter's Contour. She was in school when some punk (with no drivers license) decided to take daddy's car for a spin. He hit the back of the car behind hers and knocked it into her car. Broke her rear bumper and totaled the kid's car behind hers.
Estimate to replace the bumper, $776.36. Had a check from Daddy's insurance company within a week.
Plus, even if it were in the parking lot her insurance pays. But you can't be charged with an accident in a private lot.
Christine