It's a unconventional outtake. That's the point.
Beowulf's gimmick (one of them, at least) is a neutral grapple that can lead to several options. While people usually associate it with side-scrolling beat 'em ups, the technique has already been implemented in a fighting game (Hinogami Goh in Virtua Fighter 4). Beowulf just happens to have his outtake as a option for the grapple. Would it be any different if the outtake animation were a single strike, like a dropkick?
Or imagine if Fortune could use her outtake as a rekka option. It's practically the same principle.