[Graham Boak]

It is also quite likely that the paperwork was placed on a lorry which simply didn't make it back to England. It could have been burnt deliberately, engulfed in the flames from a strafing or dive-bombing attack, soaked in water if the lorry was used as part of an improvised pier, or just abandoned and destroyed as part of the rubbish dumps by the victors, or by those made to clear up the mess.

However, depending upon the thoroughness of the ORBs, I think the original poster is underestimating the value of these to German intelligence. Information on the aircraft serials, the names and ranks of the pilots, the confirmed losses, are all grist to the intelligence mill.