If Dubois catches Usyk with a bomb (unlikely I know), things would get interesting. I think the only chance Dubois has of winning, is to go all out attack from the first bell. To hit him with every shot in his armoury.

Anything after 4/5 rounds, Usyk will box him to death. DD doesn't have the staying powder of Usyk, who is one clever dude in the ring.

Predictions x 2....

Usyk with a stoppage in round 6

Dubois K.O of Usyk, round 2 (the only hope he has)