Mane also plays the wing while Origi typically plays as a striker. He has to compete with centrebacks for aerial duels which are much harder to win, obviously. He's also a bit more isolated in that sense which explains the not overly dramatic 13 pass difference. Origi's rate stats are fine, not that they matter a whole lot. If he takes 1 shot a game and scores a goal every 95 minutes that's still good for the team, and it could mean he's not wasting possession as much (which is what a missed shot generally does).
At the end of the day if he plays like he did yesterday that's a good thing. 3 shots, 5 dribbles, 4 aerial duels won, 1 goal, and a lot of hustle.