You’re not offering the same thing to the publisher and the celebrity. To the publisher, you’re offering your version of certain currently unknown events that t

You’re not offering the same thing to the publisher and the celebrity. To the publisher, you’re offering your version of certain currently unknown events that they may be interested in publishing. You’ll need to disclose the basic facts first before they will know if they even want to buy. To the celebrity, you’re offering the promise not to disclose even those basic facts to anyone, even to explain what it is you’re offering to other parties. Whether the medium is a book or a newspaper or a website is legally immaterial. Thinking about the information as news is just useful because no one owns the facts, only their particular descriptions of them.