User blog comment:Miskos3/Fairy Tail Chapter 367: Jellal vs. Oracion Seis, Review/@comment-4449950-20140118064540/@comment-7418318-20140118100135

Regarding Elfman... His eyes are kinda suspicious looking at the moment, so I'm not so sure about him being able to act as a spy.

He's probably been sent there to underminde FTs morale. First they have to fight one of their comrades and to make matters worse they have to assume that the same happened to their other friends as well.

So instead of just breaking them out of prison, FT has to assume that they'll have to go to Tartarus HQ, actually defeat the friends they want to rescue and then carry their unconscious bodies back to the guild to attempt to break whatever control they are under.

That's ought to be bad for their fighting spirit.