This only makes sense if King Queen and Jack are the only fights Oda intends to show from this point onwards. Whenever Luffy reached Crocodile, Lucci, Arlong, Doffy, the final time Oda showed at best 1 or 2 fights. Which means Hawkins, Perospero, and Fukurokju are going to be inconclusive fights.
Clearly Oda wants to set up this fight and potentially end Yamato and Momo's involvement in it sooner rather than later. This is potentially due to Oda wanting to use Yamato and Momo somewhere else down the line.
For example:
- Momo may be used to save Onigashima (likely), get Ame from Tengu, and potentially slay Orochi 1 last time
- Yamato may get sent down from the roof to help on the performance floor, which consequently may be due to the intention of Jack surviving his fight with Inu and potentially winning.
To me it's odd that with Sulong being a very time limited form, Oda didn't finish showing those fights with Peros and Jack immediately. This may signify that they don't win, but I don't think it means that those fights, plus Hawkins or Fukurokuju won't be "conclusive".