They signed him, played him for a few games, and very quickly realised that he's a terrible technician, hence willing to lose him for half of what they paid for him a year earlier. That doesn't happen to very good players.
We needed a 6 under Ange, with the suicide defending. With a normal set up, we need a ball carrying 6 that can tackle a bit, as in not the only thing they can do. Playing Pal invites pressure on us because he's just absolutely shambolic on the ball. And we can't move the ball forward.
He goes off or doesn't play, and suddenly we can move the ball a bit, not much because we're still handicapped by Frank's "tactics". Pay attention next time you watch him, he's dreadful.