Auto Insurance Claims: Brand new BMW backed into!, BMW owner, BMW driver

Question
I just leased a brand new BMW 750 4 weeks ago and have already got into an accident!  I was in the process of reversing out of a parking space at the local Costco (California) when another car doing the same hit me on the left passenger side tire/wheel well. The other driver insisted it was not her fault eventhough she clearly backed into the side of my car (T-bone fashion).  I told her that the damage to my tire/wheel was minimal and that I would take no action. The damage to her car was more severe than mine. After 10 minutes of discussion she finally came to her senses and realized that it probably isn't every day she gets to hit an $85,000 car and get away scott free so we exchanged insurance information as a formality but agreed in principal not to take any action against each other.

Two questions: 1) eventhough we agreed not to take any action against the other, if she files a claim against me does that put her at some advantage if I take no action?  2) While the damage was minimal to my car, the car is on lease and the dealership may ding me for this when I return the car in 3 years. Should I just file a claim with my insurance carrier? What if this woman continues to insist it is not her fault?  Who determines fault? We have the same insurance carrier - does this matter?

Your help on this is greatly appreciated!

Tom

Answer
It is so ironic that I received this question from you tonight as I was able to share it with my attorney and psychologist friends who who happened to be over this evening.

Given this, I can only suggest that you resubmit this question after having someone else read it for you.  It may be a good idea to choose a stranger as your own friends may be as pretentious and disgenuine as you seem to be.  Either that or they hang with you to have something to talk about when you are not around.

We did appreciate your out of touch representation of reality though.