25MAY44 mission of 301 BG (15th AF) was LYONS, France.Described as "uneventful".
Returning from mission appx 20 miles from base (Lucera A/D #8) 42-31605 (352BS/301BG) had a MAC (Mid Air Collision) with 42-31853. (853 was 32nd BS/301BG).Notes for 853 indicate "10 KIA". (No casualty notes for 605)
440525B-17G42-31853 32BS301BGKMAC Pilot: McCarthy, Richard D 440525B-17G42-31605 352BS301BGKMAC Pilot: Bogar, Charles R
Both pilots are listed KMAC which translates as Killed/Mid Air Collision so the fact that no specific casualty notes for 605 were found is a matter of bookkeeping rather than anabsense of casualties.
There are four members of 352 BS still buried at Sicily-Rome, including Klein.
The reason that there is no MACR is that the crews were not "missing".This would be classified as an "accident".