Yes, he'll be an RFA, but still. You know Lou, "When you have time on side, you use it."
But looking at the Devils history of bringing up junior try outs make me think he sticks. We just don't have the depth to want to send him back. He's made some mental errors, yes, but we just don't have the depth.
Edit: I think the fact that Zubrus is essentially billeting him goes a long way. Having a young kid like that on his own is very difficult to want to do for Lou. I know things like that weigh on him, because a good hockey player is important, but a good person is just as much to him. Much like the Swedes being watched for by Hedberg/Tallinder/etc. If Matteau doesn't have that connection with Zubrus, I'd be leaning much more heavily to returning him to Jr. Not to mention he's got a father than can help him cope much better than most families...