Sure, he was wrong. The treasure came out earlier. But there was no reason for it to come out so soon, especially when Germany just got it very recently. All we could do was assume, and all we could base our assumptions off of was past experience, and that pointed to the conclusion of the treasure not appearing for a while. Almost nobody expected it to come out before the end of the year, and for those who did, it was merely a lucky guess, that's it, because there was no way to predict it was going to happen this way. Many people are happy that it came out so soon, and that's great. And, while many people hoped it would come out before the end of the year, expectations and hopes are two different things; one can hope something comes out soon, while expecting something entirely different, which was the case for the majority of players.

Basically, his assumption was wrong, and yours was right, but no need to hassle him about it, when his assumption, although wrong, was the most logical. He should not be blamed for thinking what he did.