My older sister and her fiance were planning for over a year for their wedding to be this month. Obviously, they can't have the wedding as planned, but they still would like to get married, so they decided on a Zoom wedding where all of the family and friends would just call in to watch the officiant, my sister and her fiance. My sister didn't want to be in charge of hosting the Zoom call because she thought it would stress her out, so she asked me and I gladly accepted. She and her fiance decided to invite everyone they originally wanted to and it was a very big list. When we were going over the list, my sister mentioned to me that she wanted everyone else to be muted for the majority of the wedding as she was worried that others would talk over her and her fiance and could overshadow them on their big day that was already scaled down. However, her and her fiance said that I should unmute everyone at one point so everyone could talk and have a nice time with each other. Fast forward to the day of the wedding. Everyone is muted during the ceremony, which goes great, and so I then unmute everyone and ask to please raise a hand if they like to talk so it doesn't get confusing. My cousin starts waving his hand crazily and he's with his long-time girlfriend. He's a very gregarious guy, so I was not surprised. Then he says stuff like my sister and her husband are such a great inspiration, it's giving me the courage to do this. Then turns to his girlfriend and pulls out a box that is the size of an engagement ring box. I immediately saw this as him trying to steal the spotlight and booted him off our call. Then I quickly announced that my cousin had technical difficulties and would not be joining again. Everyone else accepted this and went about talking, and my sister and husband did too. The rest of the wedding went smoothly, except for the fact that my cousin kept texting me angrily saying that he had finally wanted to propose as a surprise with family all around and I ruined it. My aunt and uncle texted me the same. Am I the asshole?