I have been looking for this fight since a long time and even though I live close to germany I was not able to locate any footage. I contacted different german TV channels and asked if they have the fight in their archives. I also contacted Tobias Drews (the german commentator on RTL who commentates the Klitschko fights) and he looked up the DSF (sport channel) archive but also did not find anything. Scholz is known as one of the best german boxers ever, has only 2 pro losses: one against Humez which he avenged and the other is the Harold Johnson loss which was super close and some people say Scholz won it. The fight was filmed.
Ive got a bunch of footage on Schulz. He was a good fighter. I have a few minutes of the fight that was shown on German or Austrian TV ten years or so ago.
Hallo Baclava, yes, Scholz was an excellent boxer. A southpaw and counter-fighter. As far as I know he was too defensive in his fight versus Johnson. My source is the book "They Never Come Back" by Oskar Klose and Kurt Schauppmeier. It was published in 1972 after a famous TV-series in Bavaria.