LOL- while I normally wouldn’t answer this, because people specifically DM’d me last week asking about seating, I will say that the two people in question were seen sitting together by several people.
I can also say that people were moving around the room talking to each other and sitting in each others seats as the evening went on. For example, one of the people at my table had to sit in another seat for quite a while at one point because someone had come to sit in her seat to talk to someone else at our table when she stepped away.
This was a big group of people who for the most part knew each other and were moving around all night to talk to each other and network. So is it possible people were sitting a different tables at different times that night - of course. But it is also confirmed they were sitting together for parts of the program as well. Anyone who has ever been to one of these types of events knows people move around to talk to people throughout the evening - it was a dinner in a ballroom, not assigned seating at graduation.
There is no mystery here or anything to debunk - I just wanted to share with the fandom what I knew firsthand and had confirmed with others who were also in attendance. :)