Don't need a linebacker. Even if they did, would rather have just kept Mo Lloyd.
A linebacker can never save a bad defence. Freeman couldn't do it last year, not even close and he was astoundingly good. If your d-line gets no pressure and your secondary can't cover, Ty Jones, Mike O'Shea and Dan Kepley all in their primes will not save your defence. However, average linebackers can look like stars if your d-line and your secondary function properly.
So no, Diamond Ferri can't help this team as far as I'm concerned even if he was a nice guy. Greg Peach or Aaron Hunt or Bradon Isaac or Lin-J Shell would have been nice. Maybe Odell can help this defense. I am hopeful.