Erroneous stock footage
During the big raid you can see stock footage of German pilot punching out. Right after that you will see a quick to Second shot of P-47 firing its machine guns.
As we know the P-47 did not have the range to get into Germany the way the P-51 is did.Anyway, bomber escorts were deemed unnecessary as it was thought that the B-17 and the B-24 had enough armament to keep them safe at that time.