The story of the Kaiser paroling a POW to visit his dieing mother was interesting, but not uncommon. Reading period accounts of British POWs, they often tell of being granted parole, that is they were allowed to leave the prison camp, for various reasons, provided they promise to return, there were apearently very few cases of breaking parole, as it was a great oppertunity for the POWs to work out escape plans. Parole was so common that one British POW wrote that German subjects were not allarmed to see British soldiers unaccompanied in Germany.
This was also fairly common in the US during WWII, there was a POW camp near here, and a fellow who was a boy at the time of the war tellin about a US camp guard asking a German POW to take over guarding the other POWs, and giving him is rifle. My mother also tells of picking up POWs where she grew up, to do field work, turning a group of German POWs over to a 15 year old girl hand to show some confidence in the integrity of the POWs.