The promoter's call comes in the wake of Whyte being cleared by UK Anti-Doping (UKAD) after initially being charged by the body for testing positive for a banned substance.
After beating Oscar Rivas on points in July, Whyte was provisionally stripped of his WBC interim title and status as mandatory challenger to champion Wilder by the sanctioning body.
However, the Briton was on the undercard for Anthony Joshua's rematch with Andy Ruiz Jr. and, ahead of Saturday's victory over Mariusz Wach, UKAD announced he had been absolved of any wrongdoing.
Whyte said he had "been through hell" and Hearn insists the 31-year-old ought to be immediately reinstated in the WBC pecking order.
"Dillian should get the mandatory position for the winner of Wilder versus Fury [in February]," Hearn told Sky Sports.
"We go back to the WBC now and make sure they give him what he was supposed to get.
"In my opinion, they took it away unjustly, so now, bearing in mind the results of the case, they have to reinstate him immediately, and it should now come for the winner of that fight."
— DAZN USA (@DAZN_USA) December 9, 2019