When did Jorgen know? Spoiler
How long before the wedding did Jorgen know where Jacob was in India?
I've got two theories. First, and more likely, he knew exactly where Jacob was from soon after he hooked up with Helene many years earlier. He kept it from her until he needed Jacob himself, because he was about to die. This was hinted at in the film, because he knew all about Jacob's past failures in India.
Second, and much less likely, perhaps he really didn't know who Jacob was and had invited 3-4 other Jacobs to the wedding from India and elsewhere! He then waited to see who took up with his wife. He did say early in the film that he had to to decide between 4 or 5 projects.