Hi !
These victories are mentioned in
USAAF (European Theater) credits for the destruction of enemy aircraft in air-to-air combat World War 2 by Frank J Olynyk (published by the author May,1987) and on The Air Force Historical Research Agency website (
http://www.au.af.mil/au/afhra/avc/avc.asp)
Perhaps the planes in question only received minor damage.
Best regards
Luc