How is Samuel's age used as an example of good luck in Chapter Six of the novel, Blood on the River?

In Chapter Six, the company stops on the island and Samuel attempts to choose hatchet work clearing a path through the jungle—he wants to work with the adult men. He is sent back with a blow by one of the older servants. He must do "women's work" instead—scrubbing pots. It turns out that this is lucky for him. The men actually suffer terrible pain because they followed the gentlemen's orders from the poisonous tree. In effect, Samuel is saved at the time from the pain of manhood. He isn't ready, and that's good luck for him.