Is it permissible to pray in a mosque built on a graveyard where human remains were later discovered, out of a desire for devotion and to avoid issues of imamate in another mosque?

The mosque that was built upon graves that were exhumed is permissible for prayer, because the mosque of the Messenger of Allah, peace and blessings be upon him, had graves in it which were then exhumed. If traces of graves are present outside the mosque, there is no harm in praying, and whatever the case, this does not affect the validity of the prayer. Mosques vary in superiority based on the number of worshippers and their virtue. It is permissible to follow an imam who recites well and establishes the prayer, unless his innovation amounts to disbelief, as the Companions prayed behind wicked rulers.