"You can't handle the truth"
David Moyes signed him twice so i'm guessing he rated him, and LvG started him in the FA Cup Final(ahead of Lingard, Schneiderlin and Herrera), and Jose started him in the Europa League Final(ahead of Carrick, Rooney, Lingard and TFM).
Now there's always the possibility that LvG and Jose started Fellaini over more suitable players(see brackets) in the Finals just for the hell of it, or maybe they had placed large bets on him being in the starting XI and had an unfair advantage, or maybe just maybe they like Moyes they actual rate(d) him.