Avis unethical behaviour - theft Columbus Ohio

We hired an Avis car from Columbus (OH) international airport and brought it back to the Avis at Port Columbus airport on the 10th August at 17:30. I forgot my backpack in the baggage and realised about half an hour later. We called the office and was told the bag was found but when I went to collect it my money was missing (8, 300USD) and the front zip was half open. The police have been informed and a case was opened. It was stolen by one of the Avis's employees. I just came to country for research fellowship in a cancer center. And that money was for buying a car. I think the Avis company should be responsible for this situation. I called the police officer and he told me despite 10 days past from the event, still avis did not send the camera footage to him. I can not check, police officer can not check the camera records. And i am sure, there was something in the records.