Ok here's another DP:
Picked up a car from FLL. I did stop by the counter to mention the fact I was on third party booking (Chase UR) but I am EC EE. I told her I had a Standard car reservation (it was less than Midsize for some reason on Chase portal) but I need a minivan or large SUV because my sister is visiting from out of town. She said for third party booking, I wouldn't be able to choose from the Executive aisle but she walked out to the lot with me and pointed at a Nissan Pathfinder which I gladly took. I gave my EC number to the gate agent.
Now even though I stopped by the counter, at no point did I mention my name, reservation number or anything to the lady at the counter. So I guess your Executive status is tied to your DL # which is a fantastic feature with National and another reason why I love National.