Wiki says Manon drops Triple Throw book, but the drop table says it doesn't. Which one should I use as a reference?

Good catch: the website's drop table had fallen out of date while the in-game Monster Book and the wiki stayed current. It's rebuilt from the game's own tables now, so Xerxes is listed and Manon shows the Triple Throw books, like every boss. Use the in-game Monster Book or the updated pages; they all agree now.