The confrontation between Kaidou and Shanks occurred, Shanks and his crew fought against Kaidou and King, it is stated that the fight happened.
The Fight happened > It was interrupted by some factor.
Kaido and King really got into a fight.
The location where the fight took place is unknown, from the information we have had recently it is clear that Wano was not the location, as Shanks stated that the only time he was in the country was when he came to leave Oden.
Kaidou isn't bad at fighting at sea, it's the opposite Kaidou is the worst nightmare, Shanks as far as I know he doesn't know how to fly, on the other hand, Kaidou knows and has Aoe attacks of great magnetudes as his last breath of heat that is scaled with the ability to burn an island completely, he has his blades of wind and his tornadoes, his tornadoes at sea when in contact with the sea can cause serious deformations, giant waves, dragging ships and much more, in addition to his attacks of rays.
The fact that Shanks at least assuming here doesn't have the ability to slash fire would make this extremely bad for him, because Kaidou and King will spam attacks AOE.