I don't know, but maybe the buyer didn't get suckered, maybe they can read and know what they have got. If someone can't build a franken, has no idea where to start and has never heard of this place, where else are they going to get a gilt 5513 for anywhere near that price? As genuine pieces become ever more expensive I can see really good frankens becoming valuable in their own right.
Not saying I think it is right or wrong. In the end it is the market that decides that and anyway I have never sold a watch in my life.
It happened with cars. It is easy to sell a franken Ferrari, fully declared as such, for up to half a million.