Incorrect information causing confusion and loss of personal goods

Rented a car from 27/7-23/8. I unexpectedly had to make an urgent trip to Namibia from 16-23rd Aug on 13/8 I phoned to arrange what to do. I was told by Keegan to bring the car in and park it at CT international while i was away, on my return i would get the exact same car. I mentioned i would possibly need to extend it since i had to make this trip to Namibia. He confirmed I could extend the contract if needed which would be done on my return on the 23/8. As I was not returning the car I did not do my usual thorough check to make sure i had removed all my belongings. I was also told to not take the car to returns but to bring it to the parking where i had collected the car. When i got to the airport collections parking on the 16th I was told by Daniel that I could not do this and I must return the car and I could not park it there. I mentioned I had arranged this with the call center and I did not have the time to do all the checks which occur on returning a car as i was not expecting to be returning my rental. I started to panic, time was running short for me to check in. He then offered to drive me to departures and dropped me off and that he would check the car in, i was grateful. At this stage i had completely forgotten to check if i had left anything in the car...... It was only much later in the next day when i realised I had not checked my car and realised I had left this tiny iphone usb in the slot of the car. Today I also recalled that I had kept an all purpose tool similar to a leatherman in the space at the back of the gear lever