It's hard to tell.
- Luffy's not fighting two top tiers (still hoping Kizaru really is a top tier) 1 vs 2, so it's not option 3.
Conclusion: Not option 3.
- Luffy's objective is to defend Vegapunk and gain time for him to get to safety (along with the rest of the SHs), and Saturn's objective is killing Vegapunk and Nika, both of which are in front of him. Unless something unexpected happens to Saturn, he's fighting Luffy. It might be the ancient robot keeps Saturn busy while Kizaru fights Luffy again but it's likely as soon as the robot gets there the SHs will just run away and that'd be the end. Saturn is the major enemy here now, and depending on the robot's strength Kizaru might also be distracted by it.
Conclusion: Likely not option 2, albeit not impossible.
- Either Kizaru stays down, Kizaru confronts Saturn (if he does, he dies unless he dips with the SHs, but that'd be a pretty weird development) or someone not named Luffy keeps Kizaru busy. As much as I'd support Zoro doing that, as long as Kizaru's objective is to get to Vegapunk at all costs and not just to defeat his opponent, I don't think Zoro can keep him from running away from him (unless he has already surpassed Rayleigh).
Conclusion: Likely not option 1 because what does Kizaru do if not fight Luffy? Have a change of heart and join him to save VP?