User blog comment:Honeymochi/So Soon/@comment-48285-20140327194951

The reason why it went into the CA arc instead of following what happened to the Phantom Troupe is because the story is revolving around Gon. If Gon had followed the Phantom Troupe, then the story would have switched to the Phantom Torupe. However, Gon didn't know the Phantom Troupe was even in G.I let alone there being a Nen exorcist in the game. So, that's why it didn't follow up with the Phantom Troupe.