Vampire Basics
The reason the two boys had decided to pay Logan a visit right after their classes wasn't just to check up on Peter. A while ago Fex had said that he would teach Quinn how to use the vampire style of martial arts that focused on using their hands and fists as weapons.
At the time, Quinn didn't trust Fex too much. So he came up with the idea of allowing Logan to record Fex's ability, and upload it to the games private server. This way Fex would not be able to control Quinn's body and make him attack his friends, but he could use the ability inside the game to teach Quinn how to fight.
At this point, the two of them had gotten a little closer, and Quinn actually felt that even if they were to do this outside of the game, Fex would bring no harm to his friends. There were multiple opportunities when Fex could have done this, but he always chose not to and had helped them out greatly.