Based on the contributions on Chargemap and &Charge, it seems like these chargers are in the public underground garage.
A wide angle shot published in July 2022 to &Charge shows 8 green parking spots, and all seem equipped with chargers. Based on the closeups, chargers 1-4 visible on Swisscharge are the 4 to the right, numbered right to left. There's no signage in front of the other chargers indicating any reservation. Unfortunately there's no closeup of the Zaptec faceplate to see whether they have any sticker.