What should be done if the Hafiz of the Masjid does not follow the Sunnah?

assalaamualakum respected mufti.
i am a regular musalleeh in our local musjid.all praise to ALLAH,this is only possible through his mercy and favour upon me.recently our imaam/aalim has been allowing a haafidh from our area to lead the salaah sometimes.the haafidh outwardly seems to be pious but i know and can prove the following
a)listens to music/television
b)uses vulgar language/loose tongue
c)visits places of nudity/haraam e.g. sun city
d)does not repay debts
e)not always in sunnah dressing
should i just ignore these factors and performm salaah behind him?