I know that you're already doing what has to be done and I can't give you wiser advice, especially knowing that dealing with such matters must really not be something "pleasant" for you.
All I hope is that your watch (via this thread) becomes the most popular on the net. I imagine it can't be serviced at Lange anymore.
Aq will react if they see they can gain something (image) by helping you or if the cost is too high (by not helping you).
If I remember well, the Hotel Drouot was closed for a while because of frauds.
Indeed, in France, their behavior is like becoming complicit in the theft: hard to think it may not be considered as such abroad.
Hope this will end the right way, with a happy end as a story you can tell during GTGs.
Cheers, Mark