The Khajiit walks off into the shadows with the bomb and becomes almost completely invisible. He cracks the bomb open on an empty mead bottle and fills the bottle, then pours some wine into the bomb.
He walks back over to Mithas and hands him the bomb. "That seems to be a powerful poison. This one congratulates your alchemical skills. As thanks, have this mead." He hands Mithas the bomb and the bottle filled with poison.