Perhaps by being a pain to the Goons.....their attention was focused upon him and his antics rather than other endeavors.
His antagonizing conduct may have been useful in that regard.
You suppose there are those that were confined with him that had the same mixed reaction to him in the POW Camps that they had before being imprisoned?
During the Vietnam war we had a Special Forces Officer, Rocky Versace, captured by the NVA/VC and held captive in the jungle of South Vietnam.
He was such a pain for his captors....that in the end they murdered him.
We also had a young Air Force pilot, Sean Sijan, who evaded capture for forty-six days before being captured after being shot down.
He continued his resistance by attempting to escape several times before dying due to injuries incurred during his escapes and resulting severe beatings and torture.
Both received the Medal of Honor for their actions as POW's.
Different Wars....different enemies....different repercussions for failed escapes.
Until the murder of Fifty escapers from Stalag Luft III ("The Great Escape") punishment was usually some solitary confinement in the "Cooler" as in general the Germans until late in the war were not very brutal in their treatment of Interned POW's from Western Forces.....not so for those from the East.
http://www.axpow.org/vietnamescapes.pdf