Walter,
Don't want to pre-empt your gripping tale, but (supposing your escape attempt to have failed), did you go on the Long March at the very end ? I had a fellow ATC instructor at Shawbury, an ex-nav who did, and he told a harrowing tale.
Seems the Germans wanted to hold on to their prisoners as bargaining counters or hostages, when it would have been much easier for them to leave them behind to be liberated by the advancing Allies. In my friend's case, a squadron of Russian tanks reached them first, the Camp guards had already fled in terror, the tank commander detached a tank which drove round the barbed wire perimeter two or three times to smash all the fence posts and grind the wire into the ground.
Then the Russian tank crew said (in Russian barrack-room language, I imagine), "Off you go, if you don't mind, chaps !", left them to it, and roared off in headlong pursuit to the West.
Danny.