Try looking at it this way:
When it comes to the SHs, their main fights every arc always happen before Luffy finishes his battle with the main antagonist
i.e Zoro and Sanji beat their opponents first before Luffy beats his.
And according to Mihawk himself, becoming PK is HARDER than surpassing him (WSS).
So for now, I would say Zoro achieves his dream first. Probably the SHs will have an encounter with Cross Guild or something while they race for Laugh Tale and thats when Zoro finally challenges Mihawk once and for all.