The 21-year-old was recalled from his loan spell at the League One outfit by new Wigan boss Uwe Rosler on Monday.
Dicko, who has played four times for Wigan this season but has not featured in the Championship, was set to remain with Rotherham until January.
The Frenchman has been in red-hot form for the Millers, scoring six goals in his last five appearances, including two in Saturday's 3-3 draw with Wolves in League One.
The player's agent, Christian Emile, has admitted Dicko was in the dark about the recall at the DW Stadium and hopes Rosler will give him a chance in the first team now he has returned to the club.
"Nouha was happy to be playing and scoring every week at Rotherham," Emile told Sky Sports.
"He was never given the opportunity at Wigan despite proving himself in the Championship when he scored 10 goals on loan at Blackpool and Wolves.
"It has come as a complete surprise to me, Nouha and Rotherham that Wigan have decided to recall him today via Twitter.
"He has bagged six goals in five consecutive games at Rotherham and naturally this has attracted much attention.
"With Nouha's contract expiring at the end of the season, I can only view this recall with a lot of suspicion.
"I hope that I am proven wrong and that the new manager has recalled him for the purpose of playing regularly."