First, I identify with your enthusiasm and perhaps impatience. Seems like you went in gung ho without preparation and with gleeful abandon. \Bravo
Couple of points, gleaned over a few years experience.
The words reputable and auction house are not usually in the same sentence. I am not criticizing them, rather we should not expect them to be reputable - they are a sales organisation, not your friend. Some individuals will be highly knowledgeable and reputable, but if they are those two things they usually leave to start their own thing.
Second, do not, in a million auctions, expect as a newcomer to buy a correct 10k Euro 1680 beating dealers who know what they are doing, and have been doing it for years, and its all they do. A well seasoned collector might win one, but its going to be a lot of luck as well as probably taking a chance.
Lastly, whats wrong with the OP watch for that price? To me nothing. (better than the other one your friend shows, which to me has no charm at all). True, patina is appreciated by people like me who like odd decay, and many do not. Each to their own. That said, I will echo what others have said, you paid a newbie tax. We all do.
The alternative is to go down to Antoine De Macedo and pay top dollar for something correct, and if you have an issue he will work it out to keep his reputation and profit. (He has lovely watches)
I suggest you wear it and learn. There is nothing like ownership to teach.