Gotta say I really have no idea where we go from here, but Im going to try and guess.
I cant personally see Saturn losing now considering the other 4 Gorosei are now arriving. I still think the AR will be a factor in holding them back. We have to remember that it attacked Mariejoa 200 years prior, so we know it has some connection to attempting to destroy the WG center. Considering the Gorosei seek ageless, I would assume they would recognize it and it them when it awakens, so maybe it actually holds them off for 10 minutes.
Regarding Kizaru, however much you shit on his character, its important to note that Oda consistently has him get back up. Now that he's clearly killed VP, the real question is what he tries to do next because his VAs are now the ones focused on Bonney.
We have 10 minutes until the broadcast and a very conflicted Admiral, so I would assume after the broadcast he betrays the WG and allows Luffy to escape with Bonney, Kuma and Sentoumaru. Doing so he'll possibly sacrifice himself so it can happen.
However, until that point, I expect him to keep getting back up and continue to fight Luffy. Because if there is one character that SHOULD lose this arc, its clearly the Admiral and not the Gorosei who impose this massive endgame level vibe to their characters.
Again, no idea what will happen, I thought Luffy would fight both Saturn and Kizaru with the AR, now it feels like the Gorosei are a means to an end with the Mother Flame and this arc will result in the entire world revolting against them (prompting Imu to want to obliterate everyone pretty much lol). Even bigger than this is how Akainu reacts, I cant see him not being a villain, but I question if he'll follow the WG after this point or try and claim his own power against them like the other Yonko.
Anyway, we'll see