In "The Island of the Blue Dolphins", why did Chowig reveal his secret name after introducing himself to Orlov?

It is inexplicable to the islanders why Chief Chowig gives his secret name after introducing himself to Orlov, a stranger.  Karana, who is narrating the story, expresses surprise at his action.  Everyone in the tribe has two names, one which is common and the other which is "secret and...seldom used".  The members of the tribe believe that "if people use your secret name it becomes worn out and loses its magic" (Chapter 1).  Indeed, when Orlov's and his treacherous men doublecross the islanders and Chowig lies dead on the beach after a fierce but brief battle, everyone concludes that he should not have revealed his secret name, because in doing so he had weakened himself to the extent that "he had not lived through the fight with the Aleuts and the dishonest Russian" (Chapter 4).

Although no reason is given in the book for Chowig's apparently rash action, I wonder if he might have given his secret name because he felt need of utmost power in facing the Aleuts who had come to the island.  Chowig had told Karana about "those men from the north whom (the) people feared"; the last time the strangers had come, they had basically enslaved the islanders, making them "hunt from one moon to the next, never ceasing", catching otter for the Russians to take away on their boats.  The Russians are many, and well-supplied; against such a formidable force which had previously proved itself to be unscrupulous and belligerent, perhaps Chowig feels that he needs all the power and magic he has at his disposal.