Massallah pertaining to having a Shafi Imaam

aslkm, mufti saheb if the resident imaam at a masjid who outwardly adheres to sunnah and is a hanafi. an outside imaam from another area is a shafi/maaliki, however it seems as though he trims his beard on the side. now can board members appoint the outside imaam on the basis that alot of people that attend the eid gaah are maalika/shafi?
the sin of appointing such a person will be on whose shoulders? kindly provide detailed proof and refrence. jazakallah.