User blog comment:AYET/Asking for more of unseen fights or battles!/@comment-3075024-20120301143025/@comment-3119203-20120301154801

They did say there was a skirmish I think, so it might have just been like what Shanks and Whitebeard did, just clash in a show of power. Shanks probably threatened Kaido, saying something like "you won't get away easily if you do this.." or "I'll give you some territory if you back down" or Kaido simply left.

Personally, I would want to see some kind of brawl, but whatever.