What do you mean, "false"? If we're getting our memories back, are they not ours? Surely they wouldn't return false memories to us...

[He reaches up a hand to scratch at his chin, thoughtful.]

I have to side with Alice and Shijima here. Talking with Ciel is risky. What if he uses you as a hostage? Or kills you? Besides, wouldn't executing the files play right into their hands?