I have been researching the Rudelhoffs for decades. The first thing I researched was the marriage of HAR and Mary Reger. I have a photocopy of the marriage entry and had always believed it to be Reger. A few months ago I was given a coy of the steel book and was puzzled as to why they thought it was Rugen when the entry in the parish register clearly says Reger.
Anyway my recent research into her birth and baptism clears this up as those entries in Bermondsey clearly say Reger too.
Another puzzle is Michael Reger's occupation - steel book says tailor whereas when Mary was born he was a cooper.

When I was a child my grandmother told me that HAR was a soldier in the Prussian army but other members of the family think he came from Latvia and the Steel book says
Poland and before that Russia.
Lot of research still to be done.

Beryl