I was finding this thread increasingly incomprehensible, but a glimmer of light at the end of the tunnel appears.
French and German law differs significantly from English law in a number of respects. I assume that what our putative author is mistakenly referring to is summarised here http://www.roger-pearse.com/weblog/?p=3644
It would be correct to suggest that a work of fiction, once published, is irrevocably associated with that author. English, and American law allows the commercial and authorial rights to be sold as a complete and single transaction, German and French law don't. So, if a right of authorship could be demonstrated, a contract of the US type requiring a complete buy-out of all rights would be problematical in Germany.
However I'd also have to interpret that as meaning that writing fanfic was a similar infringement of TP's right of authorship in respect of those characters, although whether he is actually concerned about fanfic I have no idea. American SF authors tend to be fairly blase about it, on the basis that accepting the free publicity is a lesser evil than the main option of protracted and expensive legal proceedings to no ultimate useful end.
However, Conan Doyle's reply applies; to the effect that there is no conceivable incentive for the original, published author to collaborate with an unpublished newcomer, since the benefiots are entirely one-sided, as are the drawbacks.
As it happens, my wife has at times worked as a "reader" for a publishing house in the UK, and her view is that most of the work submitted to her is simply not good enough and rejected on that basis. If that's the case regarding the small percentage that gets through the initial selection, and given the sheer unreadability of a lot of the convoluted trilogies found on the "fantasy" shelves, then the quality of what ends up in the bin, or deleted unread must be pretty dire