Dagny really wanted to hug them both. Hug them both, shout a rapid-fire loveyoubye, and then disappear without warning or ceremony. It might yet happen, depending upon her self-control.
But for now, she was sticking to plan. Chat, excuse herself, 'disappear' the normal way through a door. You know. The way people did.
"Soooo. Random, but. You know what I've always wanted to do? Hijack a float Ferris Bueller-style and sing Danke Schoen to confused parade-goers." It was a topic change? It was also the first thing that had come into Dagny's head, and was apropos of nothing at all.
Maybe she would loveyoubye. Dagny hadn't come up with a good exit strategy.