It seems people who comment didn't actually see the Downtown show.
Minami didn't ask JKS, she said her "question" to the other MCs, when they already were walking to another place to meet another star.
So JKS couldn't actually reply to her.
Yes, he was not very kind with her on the show, but this just makes the things look like Minami was taking some kind of revenge
And, about the TOPIC - no, he didn't have PS!
His nose is natural and everyone can watch the hilarious episode of "Kneedrop guru", where Jang Keun Suk proves it