The dreaded RDU. They don't like to give upgrades no matter what your status. The one time I rented from there as a Platinum, I was "upgraded" from a F to a YF Impala. I agree you should go online and do a billing dispute with Hertz first. They will usually fix it back to the price of your contract. At this same location, I booked a car under the AAA rate with a free additional driver. Once I returned the car, they charged me for an additional driver. When I asked why I was charged, they told me AAA doesn't cover additional drivers anymore. I went through the billing dispute on the Hertz website and was refunded in about 7 days. Hope it works out for you.