Three things:
1. If Mihawk is not helping the WG, then why would he fight Zoro when the SHs face off against the Marines?
2. Zoro vs Fujitora and Zoro vs Kizaru both have legit groundwork. Either or both of them happening are possible. Not in the same arc (if both happen), but both are not baseless.
3. Fat and slow characters like Wadatsumi, Oven and Queen are the only kinds Cook can beat on-panel post-TS, tho. So, maybe we can count on Cook vs Sentomaru, after all?