He had nothing to do with that. The famine was largely caused by natural disasters, crop disease, Japanese invasion of Burma, and incompetent local beurocrats.
I would also imagine that he was a little busy with the impending fall of Europe in 1943 given the Americans did not join the war until 1944. I also looked at additional accounts and it appears the local government didn't even declare a state of emergency, so how would he have known?
Or that Europe's "fall" was pending in 1943. France had already been taken over by then, while the Battle of Britain had secured England's airspace, and Russia was pushing back in the east. Germany had seen its high water mark at least two years before.
When would he be the cause, then? When he personally burns down granaries?
I think if you were warned your actions might harm millions of people and you ignore those warnings you are a cause. Perhaps not the only one, but your choice is part of the problem.