[Franz von Werra]

The CWGC website seems to be useless in this case. As you have experienced, all searches come down to nothing.
Sorry I have no other information other than that posted here, which comes from a newspaper article that first dealt with the case nine years ago. Now I'm close to obtaining another JAG file detailing the shooting of a POW in the area close to the capital city of the Italian Social Republic. The date and place match closely those referenced (pretty hazily) in the article. So maybe this is it.