[Franek Grabowski]

Currently I am looking for German pilots who baled out from Fw 190s in April 1942 in France, I understand your problem.
Well, your baseline is the claim. All you can do is to research Allied operations of the day in order to make a clear view of the mission as well as other missions of the day. Then you have to research Luftwaffe operations which is not that very easy but still you have plenty of sources both German and from Allied intelligence.
Have in mind that quite often German losses are inaccurate or misdated, I have found some combat losses that occured on the days no combats were reported by Allies. Of course no definite proof as they could have occured due to friendly fire or simply not claimed. I was talking to a pilot, who claimed he had separated from a formation for a free hunt. Together with a friend they bounced two Me 109s but never claimed them as this was a clear case of breaking the orders. I have found a confirmation from another source, I think independent enough to make the story credible.