I don't recall that being mentioned in Bernal Diaz del Castillo's "The Conquest of New Spain". I've also read "The Broken Spears", an Aztec account of the conquest which was recorded once surviving members of the Conquest or their descendants had learned written language. In both accounts, it appeared that there had been forewarning of "Gods" from the east who would conquer the Aztecs from the priestly / ruling caste of the Aztecs. The whole story is really quite interesting, but wearisome on ones soul, I would highly recommend both books if you have the constitution for it. Werner Herzog recommends reading "The Conquest of New Spain" to "... understand the hearts of men."