For a "regular" person, It seems like Bernie meets with and interacts with a good number of the major players in Hitler's Germany. In one way it makes the books more fantastic and unbelievable, in another way, it makes them more interesting. Does Kerr go to far in this respect?
He seems like the luckiest unlucky guy in the world -- or the unluckiest lucky guy. I mean the only thing he has more than good luck is bad luck. Or maybe the only thing he has more than bad luck is good luck! I'm not sure which......
He interacts with all the top Nazis except Hitler; Goring, Heydrich, Goebbels, Himmler, Bormann which is correct for time and place given his position as a top detective.
I have never felt BGs interaction with the upper echelons of Nazi Germany to be improbable. They needed his assistance, someone competent and reliable. Get that rep and you will be summoned forth.