checked it today, and the footpath is still there, and open for most of the day. It is significantly more public than the footpaths going through Grabenstr 5 ("Brauerei-Passage") and Brauereistr 23 ("Rewe-Center"). 

However, I could not find Praxis Dr Volker Weber. If I remember correctly where it was (at the very end of the building, closest to the parking lot opening to Grabenstr), it has been replaced by  "OGPaedicum Medizinische Versorgungszentren", the website is www.ogp-nrw.de