So from the viz,Kinemon&Denjiro plan to lead the troupes from the sides while Law brings the rest of the scabbards through the rear gate.Once there,law uses his powers to send the scabbards onto the island for them to land the final blow on kaido.
So like i said earlier,the scabbards are truly the ones set by the plan to deal with kaido.
Not law,not luffy,not zoro,not kid..
But when the scabbards are captured/defeated,the SNs are going to take the stage ;not before that though! !!
Meaning guys like luffy are going to have many warmup fights before the kaido confrontation.