What is the ruling on accompanying corrupt relatives, and are they considered bad company?

You must advise your relatives concerning the abominable acts they commit. If they do not respond, then boycott them if boycotting benefits them. However, if boycotting does not achieve the desired benefit, then maintaining ties remains obligatory. Maintaining ties does not mean companionship, but rather that which fulfills the obligation of kinship, especially if companionship leads to harm in religious matters.