What if the "Lake Placid" croc took on the giant mutated bear from "Prophecy"?
In any event, a Nile croc can still outweigh a kodiak by as much as 500-1000 pounds (1000-1500 lbs for the bear; 1900-2400 for the croc). Crocs also have perhaps the strongest biting force in the animal kingdom. If they fight in water deep enough for the croc to maneuver, but not so deep that the kodiak can still maneuver, I see the croc winning.
I'm not sure if the bear's claws could penetrate the croc's armored skin; neither do I know if a swipe of the croc's tail could break a bear's leg. The bear's best bet might be to stomp down on the croc, like how a polar bear breaks into seal dens. But that might work mostly if the fight is on land.
Would be a cool fight, better than Silverback vs (and loses to) Kodiak. 😎