It's gonna be both Neko and Sanji's group, watch.
Neko and Shishilian will jump Pero at the exact right time, while Sanji likely attacks Queen to save Chopper. Then Chopper heals Zoro. Considering Marco is still stalling King, I'm sure Zoro will recover and fight him after.
Hopefully Chopper is set up for whatever comes next, but I'm curious about this side effect Caesar mentions