I just don't know what you're getting at, other than making assumptions with no facts at all behind them. There's no reason to assume he has been promised a spot and another move needs to be made. No reason to assume that, if he does, the move would end up making his addition a net negative.
Teams frequently bring in extra bodies in training camp, and most of them end up getting cut and not making the team. The safest assumption is right now they wanted an extra body for training camp, with nothing beyond that certain in any sense.
I look at it at least as a training camp positive. We can now split the team into 2 fairly balanced 8-man rotations for scrimmages. His addition at the wing means we can shift Lou to PG just for scrimmages, and still have 3 wings on each squad. To me, this in itself is a good enough reason to give a guy an unguaranteed training camp invite.