We can't say how long anything is lasting really. If it ends next chapter or 1040, or 1045 or 1050, who knows. The whole conversation was about Kid and Law only lasting as long. Does one of them lose (imo, it can't be Kid)? Does that shift the dynamic of the fight?
I believe both of these arguments are correct. Kid will be instrumental in taking down both Big Mom and Kaido.
But seriously, it all makes sense if you're a raid failer. Kid will have a temporary victory here against Big Mom like the rest of the alliance have, and he'll also get his big moment with Kaido later after the raid fails.