Yea, I actually did give Nintendo a call. I reported the bug and they said they would work on it.
They first thought I wasn't doing the mission properly. They explained that after talking to his siblings there was supposed to be another quest in my mission log. They told me to try and switch missions, yet the other mission wasn't in my log.
After a few hours of watching tv I return to the game and sure enough, it was directing me in the direction of Koko!
So I completed the mission and continued my game..... Only to find another game breaking bug.
Yes, another. If you go into the character affinity and click on Irina, and then check her character profile, it will freeze the game. I did this after completing a mission and grinding for a few hours, I did not save. So I am right back to where I started, looking for Koko.
Yea, I have extremely bad luck with bugs and glitches. If there exists one in a game, it will find me.