Nicholls returned to action for the first time since suffering knee ligament damage at West Brom in September and came through okay after 60 minutes' action.
Former Millwall midfielder Ifill, who Wise knows well from his days in charge at the New Den, is reported to be at the top of Leeds' shopping list.
An unnamed Scandinavian trialist put Leeds ahead and Seb Carole staked his claim for a first-team recall with the winner after Ade Akinbiyi had levelled.