Visited on September 25 and charged with M-CHARGE RFID.
I had trouble finding the parking entrance. There aren't any Migros signs. At the roundabout on the main road there's a sign for "P Zentrum", that's not the name of this parking but that's the correct turn. Then you need to drive past the Zentrum parking, past another roundabout and then turn in a cul-de-sac also without any Migros sign.
Once inside the correct parking area, there are still no Migros signs, but there are M-CHARGE signs at that point. You need to drive down the many levels of the public parking, and at the lowest level it connects with the customer parking for Migros. When leaving, you need to drive up all the levels again. I'm not sure whether the public and Migros side use the same parking tariffs, but the Migros side definitely closes with the store.