Sorry, I tried Google Fu and it only gave me the info that it seems to have closed about 2 years ago.
Going down the rabbit hole I found that the owner was Markus Breuer who came to fame when he - together with his former wife and their children - starred in a reality show called 'Goodbye Deutschland'. The show followed their life in Canada. After a few years they returned to Germany where he opened the restaurant. Unfortunately there are no reputable articles about him and even the yellow press lost interest after a while. I couldn't find articles that are younger than 4 or 5 years.