Unwanted Inheritance

In 1999, Michael Packham a twenty-six-year-old doctor working in his local hospital's Accident and Emergency Department receives a letter from a distinguished London law firm, who are seeking to identify the beneficiary of the Last Will and Testament of a former German Panzer tank radio operator who fought against the Allied Forces in the Battle of Normandy in 1944. Otto Wagner, who's Will it is, has left a huge house and farm estate in Southern Bavaria to a British Army Surgeon who saved his life during the Battle of Falaise. The question is, how did a private soldier in the German army obtain such wealth? Why is an organisation of ex Nazis so keen to obtain this estate for themselves and will do everything they can in order for this to happen?