Issue with Hertz rental claim

Hi,

Thought I would ask this on here as this is regrading our car rental we had with Hertz this past February. Rented a 2016 Nissan Altima which had a good amount of scuff marks on rear bumper, scratches in other places and tiny dent on a door. All were marked off on the slip they give you and the Hertz person said not worry about light scratches. Off we went for our 17 day vacation. On the return day, hubby dropped me off at the airport and went to return the car and the Hertz person checking him in pointed out a small (approx 2in long) yellow mark on back passenger door. Hubby advised he had no idea where this came from and thought it looked like a rub mark from possible a car. Hubby said it was barely visible and could probably be buffed out. Hertz person made him fill out a claim form. Fast forward to 2 weeks ago and sure enough we get a call stating that the damage was a whopping $2100 US!! There was no dent or even scratch into the paint just a yellow line according to hubby. Hubby told the person to send evidence: picture of the damage and the estimate for the cost. That arrived and the picture they sent is a black and white photo copy that is so nondescript it could be any car and taken at any time as there was no date stamp on it. The estimate looks like they replaced rear quarter panel, rear door shell, side curtain air bag, satellite sensor etc. All for a yellow mark? Hubby also did some homework and it seems that there was a NY Times article about claims fraud with them previously. I also found some remarks similar when I google the number they call from. Hubby also went to our local Nissan dealership just to get an opinion and they felt the estimate doesn't match the picture sent. So I'm wondering if anyone else has had issues with Hertz in this regard and cautioning everyone. We're definitely fighting this even though our credit card would cover this but they certainly shouldn't have to. What have we learned? Taking pics of every bit of the rental cars from now on.

Any help will be apprecited.

I didn't find the right solution from the Internet.

References:
https://bit.ly/2sKFNTl
Data Analysis Video

Thank you.