Wouldn't really say any of them are frauds. Rodgers probably the most of the lot but he's much younger than the other two and has done well at all his clubs except Reading. Pellegrini outdid Mourinho to the title last season. LVG has been good at a lot of clubs in a long career. Similarity between all of them is they've all been 'good', rather than 'great', at the clubs they've managed.
Wenger's a fraud now, but the biggest fraud in world football is Guardiola. Has had a squad significantly better than anyone else at both his sides, but has made things unnecessarily difficult for himself. Has been dreadful at Bayern: the Champions League 'campaign' nearly featuring a defeat against David Moyes' Man United was a joke. Also I'm not a fan of his breed of joyless footballing purists.