If they are not going to use him then yes he needs to go back to St. Paul. I am not sure if we know anything about whether he can play up or here not. He started 3 games in 3 weeks and hadn't had a plate appearance in 12 days until today.
Why do you use up a 40 man spot for him and then not even use him. He did deserve some playing time, whether he would have flopped or not no one knows. This is just poor roster management, this organization really has no plan.