Visited on July 5 without charging.
The chargers are among the parking spaces designated "Restaurant, Bar, Arzt, Coiffeur, Physio - Surenweidstr. 1".
I'm not super sure what the intent is, it seems like the 4 parking spaces on the south side of the road are designated for charging, via the big sign in the middle with EV symbol and arrows pointing both ways, as well as additional plug symbols and parking ban signs with "Restaurant / Bar" vertically and "Elektrofahrzeug" horizontally. But there is only one charging connector per side, so you would always end up with 2 unused parking spaces if the signage is followed to the letter.
I could not find any QR code for ad-hoc payment. The Ecotap "serial numbers" don't match with the Partino EVSEIDs, so no idea which charger is which in the roaming data. Good luck, you have a 50% chance of selecting the correct one if you start with an app!