They would do anything to apply the waiver

I rented a car with this company, being a regular customer with them,the car back window was broken into and some personal items ******. The car was in a well secured undercover parking with roaming security guards unfortunately they say they didn't see anything. I had taken out windscreen cover and returned the car for assessment and told they charge just the admin fee. To my surprise I get a call from collections department asking when I will pay R4800+ vat. I was never even informed that the windscreen cover wont be app****, and threatened that should I not pay this I will be handed over. When I argued by saying I had windscreen cover, they noted a dent in the boot and they say it is a collision that is why I am being charged 100%. My argument is that the dent occurred due to the breaking of he window, it seems they used a *****driver between the boot and window a small mark was left in the boot. The item only cost Budget a R1000 to repair. I brought this up with them, not even the decency to acknowledge that they will investigate the matter. I can't even find complaint section in their site. I just think Bugdet will say anything for them not to pay for damages and it is wrong.