No deals with AAA, to my knowledge. At least no deals that are exclusive to them. If Aulani is running a promotion to the general public, AAA can book it. That's about it.
I agree with PPs that using your DVC points is the best way to go. Not only is it a good value with your points, but those staying on points get free parking. Renting a car is a must in Hawaii, IMO. We also were able to get groceries to help ease our food budget and had a microwave and fridge in our room (studio), and because we were on a long trip, by the time we got to Aulani we took advantage of the laundry that was included with our stay on DVC points as well.