McQueen’s character was invented as far as I am aware.
................................. ????? There is a motorcycle monument located in the square in Sagan, I don’t know if it was attributed to Mc Queen or the real person who rode it. BTW,FYI, The Luftwaffe POW camp even had a small golf course that was put together by the POWs.
There were no Americans involved at all.
McQueen’s role was a composite. The main person serving as inspiration for the character was British.
The movie was a highly factionalized account of a true event.