Sadly enough I have not read that book, but I know a lot about John Rabe. He was the head of the Nanking Safety Zone, and wrote into Hitler protesting the slaughter (calling it "bestial machinery.") I find it sad that even Nazis were horrified by what happened there.
I think it's also very sad that he was eventually punished even though he'd tried to do the right thing... if I remember right, he was tried at Nuremberg and convicted. But Chinese remember him fondly.
i dont think he was convicted at nuremburg, but he was convicted for fratenizing with the enemy and speaking out against the government while germany was still in power. he then lost all rights to rations during the war.