Why not play MDM as a d/m in front of Mangala whilst Vinny is out, he would talk him through games, I don't think Mangala is bad, just young and needs to be talked through games
He isn't young. He's an experienced player and if he still needs talking through games then that says something. We certainly can't afford to play a 35 year old defender with no remaining speed, out of position, in a role that demands mobility, just to make up for his shortcomings.
He either shapes up or he ships out. He's getting the chances to show us he can do it and on occasion he has, so let's hope for the best.