Is it permissible for the People of the Sunnah to participate with the People of Innovation in establishing a cemetery in one place?

The people of innovation (Ahl al-Bid'ah) are not all alike. Those whose innovations entail disbelief (kufr) should not be buried in Muslim cemeteries. However, those whose innovations entail فسق (grave sinfulness without disbelief) are considered Muslims, and they should be buried in their cemeteries after being washed, shrouded, and prayed over. Among the innovations that entail disbelief are: claiming that the Quran has been distorted (tahrif), declaring the general body of the Companions to be disbelievers (takfir al-sahabah), and asserting the infallibility of anyone other than the prophets.