If this arc is already underwhelming, imagine how unbearable it would become if, once again, the action was cut short and we suffered Udon 2.0 (maybe not even that) but with a lot more characters. Let Nekomamushi and company come in a critical moment if you want, but please, Oda, don't slow down the train of events now that we've known Oden's past, everybody is ready to fight and the samurais have sunk their ships because they're confident on their victory; Oden's own imprisonment was already flawed and anti-climatic, don't think you can handle it better with more and more important characters than him.
Regarding Hawkins prediction, I'd find it to be immensely more interesting that Wano ended before that month and he actually predicted some unknown future event so dangerous that the post-Wano Straw Hats only had a 19% chance of surviving.