Thornley, 21, has scored 11 tries in 20 appearances for the Warriors this season, but was left out of the squad for their game against Castleford on Friday.
That made him available for Scorpions, where he featured alongside team-mates Rhodri Lloyd and Joe Bullock on dual-registration.
Scorpions coach Dave Clark said: “I think he got his objectives out of the game.
“He played well and he’ll be looking to get back in the Wigan team as he’s far too good for this division. But it was great to have him with us, even if it was just for one game. It was good to have Rhodri Lloyd too and Joe Bullock. Hopefully we’ll have Joe for the rest of the season now.
“It’s good that Wigan can use us and give their players an opportunity to play an intense game at a good level. It’s a partnership that suits both of us.”