Hello Rolf, Thanks for the reply. Hope all is well.
During Aug of 44 when he was captured, there were only 67 interrogators at Dulag Luft Oberursel. I have been using the following sites.
The Interrogators http://www.merkki.com/new_page_2.htm
Army Air Forces http://www.armyairforces.com/default.asp
I also reached out to Schraff's son Hanns-Claudius Scharff.
As you said it is not easy but still chipping away. If you come across anything please reach out. My email is bladerunner868@hotmail.com
Louie