I actually disagree with that. Grassa is one small voice in the corridors of ICT. He has this club in his heart. He may, or may not, have had something to do with bringing Brew back but, on his own, has no power to get rid. Grassa's job is to negotiate contracts with the people identified by the manager.
If there not identified there's no negotiating. Translate not identified as not wanted.
Bennett had a lot more to do with hiring Brew than you think Alex, a lot more.
Its his job to act as go-between from Football manager to the Board, also to hire/fire whom he sees to benefit the running/success of the club.