Can Dubois beat Usyk/Parker for the WBO?

I don't see why not. Usyk is a million times better than Dubois but he's fighting above his natural weight class. Him taking an L there is just a matter of time. Parker fights to the level of his competition. I could see him lose that fight too.

Hard to say, Dubois hasn’t beaten anyone of note. If he beats Joyce, people may still ask how good Joyce was. Personally I think Joyce beats him. But anyway, he could arguably beat Parker if he shows he’s a good level. I like Parker but I think he lacks a bit of spite needed to beat dangerous fighters. As for Usyk, I think Usyk wins. Dubois isn’t going to set about him and jump on his chest like Chisora did. It’s not his style. Dubois is a more measured boxer and that probably suits Usyk a lot more. I see him having too much experience for Dubois in that kind of fight. Dubois still seems a bit stiff and fights in straight lines from mid range, probably tailor made for Usyk. As I said, I think Joyce beats Dubois anyway.

It’s unlikely to happen really, frank isn’t going to let dubios (or Joyce) fight on matchroom cards. Parker and usyk have much bigger fights they can take.

I don’t see him beating Usyk, but him against Parker is an interesting matchup.