Visited on Monday without charging.
The 3 AC charging spots are next to the Superchargers on the second floor.
Strangely, they painted 4 spots for the 3 chargers.
The chargers are pooled together with the Tesla chargers and the spot without charger in the electric spot counter, so there's no way to know how many AC chargers are really free when looking at the sign. But since the counter is only displayed inside the parking and not outside it doesn't matter much since you already entered you can go take a look.
I published more pictures on the Tesla Supercharger location. Once I implement the ability to publish the same pictures on multiple locations I'll cross-post them here as well. I don't want to implement duplicates in the meanwhile.