A corporal in charge of an entire prison camp?
That seems weird. There would have to be dozens of guards at that camp - a platoon at least, if not part of a company. An officer would be in command.
Even if it is true that Watanabe was a corporal in charge of an entire camp, why would the Japanese do that? That is very strange.
I want the doctor to take your picture so I can look at you from inside as well.