Place it as the payoff at the end of a short singing or show-off scene, after a quiet reaction clip builds the setup. Follow it with the Trololo Song for a second gag, letting the two performances answer each other in the same edit.
Über diesen Sound
This short clip captures Arin Hanson belting out Adiemus in a deliberately loud, exaggerated style, stretching the wordless melody into a comic performance that lasts just under four seconds. It feels playful and over-the-top, like someone showing off in the worst possible way on purpose, and it works best as a burst of silly confidence rather than a serious vocal.