Enterprise Rent-A-Car Fradulent claim for suspension damage Oakland California

In February 2014, I rented a 2014 Hyundai Sonata from Enterprise Rent-A-Car on Broadway in Oakland, California.  I had the car for five days and drove a total of 83 miles.  On a Friday evening after work I drove the car to my friend's home with no issues and no incidents.  That following Saturday morning, I went to get into the vehicle and the car would start but would not move. The car was making a grinding sound so I called Enterprise and they had a two truck come and pick up the vehicle.  A few days later, I received a call from Enterprise demanding my deductible stating that the suspension was damaged and I had done it.  I couldn't believe it!  There was no way I damaged this vehicle.  I didn't hit anything nor drive over anything and there was no visible damage to the car.

I was forced to file a claim with my insurance company, AAA.  In the meantime, Enterprise got the car repaired (without letting AAA inspect it) and sent me a letter demanding $1,500.  AAA informed me that if they were to pay the claim, I would be considered at fault and would, in addition, receive points increasing my monthly premium.  I told them to deny the claim as I could not afford to have my premium increase and have points on my record for three years.  Today, March 17, 2014, I received anothe letter from Enterprise, this time demanding $2,500 stating there were supplemental repairs. 

I did nothing to this vehicle and contend there was already damage.  Yes, I failed to look underneath the Sonata when I rented it and was inspecting it, but who does that?  I am an accountale, mature, respectable adult and if I had damaged this car, I would own up to it.  Enterprise Rent-A-Car is attempting to defraud me and my insurance comany is offering me no support.  I cannot understand how they could repair the car without inspection on the part of AAA and then, in turn, demand an additional $1,000 from me.  Enterprise is attempting to RIP ME OFF.  They are in for a fight!