I don't think it would be an one-on-one battle. I mean, the Warlords are very powerful but Kaidou is arrogant. He'd probably tell the All Stars and Tobiroppo to deal with the Warlords. That's why I think Mihawk, Crocodile, Kuma and Hancock would destroy the crew before reaching Kaidou.
However, if Kaidou recognizes the threat of the Warlords, then he'd intercept them along with the All Stars. So I think it would be likely:
Once the All Stars faint, the Tobiroppo (along with Hawkins and Apoo) would arrive to fight the tired Warlords. Then I think it would be likely:
At this point, Kaidou would fight at full-power what would require all the Warlords to fight together against him. So I think the Warlords could win.