I wonder if a possibility might be Lancaster PB188. Its crash site does not seem to be known and I believe there was one casualty, Albert Cyril Mathews. The rest of the crew were POWs. Mathews is listed at Runnymede.
https://www.cwgc.org/find-records/fi...RIL%20MATHEWS/
The other Lancaster that went missing that night with no listed crash location was PB356. Several (or all) of the crew are buried in Hamburg, so more than one casualty.