George,
Some info about his claims can be found here:
https://en.wikipedia.org/wiki/John_C...m_(RAF_officer)
There are other sources as well and you certainly have read his Combat Reports, at NARA KEW (Files AIR 50)
I acquired this book, believing to find more about his wartime and combat claims as well, but was disapointed. > Golley, John (1999). John "Cat's-Eyes" Cunningham: The Aviation Legend. Shrewsbury: Airlife Publishing. ISBN 978-1-84037-059-1.
However, you may know or have read his RO or Navigator's memoirs:
https://www.abebooks.com/servlet/Boo...-srp1-_-title1
As FILE AIR 27 confirm, Gomm was the first to take-off on the night you are researching. On that particular night, I also only managed to find G1+ES being credited to Cunningham's crew.
A.