Why the fuck would Justin need a celebi?
No not really. Any move you want to use on it will give it away that your Zorua accept for other dark types in which case you don't really need illusion. The only good use I can think of is leading fakely with espeon as an anti lead, so then people don't use entry hazards on you in fear that they will reflect back. But any surprise like that is ruined anyway becuase of the team preview option where they see the last pokemon in your party and Zorua and automatically know when you faking, ruining the surprise.
I have spare Celebis.