You probably have to replace the connecter. I guess there are at least 2 ways you could go.
1. Cut that whole end off of a junkyard harness You can back out the individual wires and females out of the big plastic plug part by depressing the little metal tabs on each individual blade. Then you only have to splice on one wire for the fried blade. And push the old wires into the plastic plug you got from the junkyard.
or 2. Convert all the wires over to the individual blade ends that crimp on the wire that are available at auto parts stores. Take your switch in to get the ones with the best fit.
Choice 1 would be the most robust, where choice 2 is kind of a butcher job.