Regarding options for Fury after his defeat, there's also Joseph Parker, an interim WBO champion. I don't know much about the recent affairs inside the WBO, e.g. is there any deadline for Usyk to fight the interim champ before getting stripped of the belt? But if Usyk was to vacate the WBO title to fight against Dubois for the IBF belt, then, potentially, it could open the door for Fury to have his shot for the WBO title against Parker. And if he was successful, he could then try yet again to win all the other belts back, either from Usyk or Dubois.