How do you see Zoro ending up in Impel Down?
I believe Kuma will arrive & send Zoro to "Literal Hell" this time, which is Impel Down
It will be orders of WG ofc, to send Criminals to Prison directly using Kuma's DF Powers
Zoro due to Tiresome, Injuries & Minks Drug will be unable to defend himself at all
(Kuma is a CD Slave, but he is also a WG Weapon, they can dispatch him when needed)
Sanji will either Infiltrate Vegapunk Island since he is best at such Missions or he will also be captured by Cipher-Pol or Science Division.
As for Luffy, it's possible that Fujitora will capture him just like he said he would.
During this Short Arc, Usopp's Lie will finally come true when he said "Beautiful Master Swordsman with Meat is here"
Most Readers thought it came true with Rebecca, however that Lie was clearly for all Monster Trio, not just Luffy, not to mention that Rebecca is not a "Master" Swordsman
Master Swordsman is about Shanks who will save Zoro from Impel Down
Beautiful Female who saves Sanji is either Shirahoshi (Who escaped Fishmen Island after a Villain appeared) or Pudding or even Hancock
As for Luffy, he will be saved by Meat (I will hold on to explanation of this for later)