In *Kingdom Come: Deliverance 2*, completing the "Wedding Crashers" main quest can be tricky, especially when it comes to congratulating the newlyweds. Once it's clear that Otto von Bergow won't be attending Lord Semine's wedding, you need to find a way to wrap up the quest and locate the newlyweds before leaving the celebration. Unfortunately, neither Agnes nor Lord Semine are easily found during the event.
Before you set out to find Agnes, make sure you've completed any other tasks you want to do at the wedding. Once you start your conversation with her, it will lead directly into the quest's conclusion, transporting you to Trosky Castle. Most of the additional wedding content happens before the ceremony, so you should be set by the time you reach this point.
While mingling with the party-goers, you might ask if anyone knows where the newlyweds are, but you won't get any useful answers. Instead, head towards Agnes' location. If you previously stole some schnapps from the wine cellar, finding her will be straightforward.
No matter how your conversation with Agnes goes, it will end with a man stumbling into the cellar, sparking a brawl that spreads throughout the wedding. You can either wait out the time in the cellar or join the fight. The outcome remains the same, leading to a cutscene where both Henry and Hans end up imprisoned at Trosky Castle.
That's how you congratulate the newlyweds in *Kingdom Come: Deliverance 2*. Next up, you'll want to tackle "For Whom the Bell Tolls," your next main quest, where completing tasks within a time limit can boost your reputation.