The Visitor Event Guide/Discussion.

My friend found a... unique way to deal with the JQ cube. Knowing that I was able to handle myself well in there and that he easily gets frustrated with that cube, he goes to kill himself in the cube. I was the only person left in the cube to clear it, and the game recognized that and let me clear the room myself.

So yeah... if you have anyone that sucks at the JQ or just want it done with ASAP knowing you can solo it, just have everyone else kill themselves and wait in the Res cube until you clear the JQ.

EDIT: Wait, there's a limit as to how many Uwana cells you can put in an equip? lolaww