I find this really interesting too. It does really challenge, for me, the notion that authors are primarily creating for economic returns — I think we do our students a disservice when we fail to point out the complicated interests that authors have in their expressive work.

Re the fan stories, there are already, no doubt, tons of fanfic versions of Twilight told from multiple POV. The interesting thing about this version is that it is both canonical (due to the authorial origin) and non-canonical (because she disclaims it). But while a moral rights system might support that sort of power on the part of authors, it may turn out, for various reasons, that authors are not able to make that call. See, e.g., Kafka & many others.

As with Buchel, the episode seems to evoke trademark law law and/or trade secret law more than it does copyright law:

In a trademark sense, she is being held as the source of a product that she disclaims, and for that both she and her fans deserve the sympathy and perhaps a trademark remedy, Dastar notwithstanding (though a remedy may not be practical).

Does the trade secret idea cut the other way? In a trade secret sense, she failed to take reasonable precautions to maintain the secrecy of the work; secrecy was key to maintaining the value of the ultimate product; and so on. You snooze, you lose, in a trade secret world; you can’t play Renault, gambling with the work then claiming to be shocked when you are betrayed. The parallel isn’t perfect, but the atmospherics work.