If the second target creature is no longer on the battlefield as the damage is dealt, the damage isn't redirected away from its original recipient. The same is true if the second target creature isn't a creature (or a planeswalker) at that time.
19-03-2021
wotc
The damage dealt to the second target creature is dealt by the original source of damage, not by Kor Chant.
19-03-2021
wotc
You choose the two target creatures as you cast Kor Chant, but you choose the source as it resolves.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.