What is the ruling on participating in the funeral procession of one who died while seeking help from graves?

If a Muslim dies while persisting in seeking help from the dead, it is not permissible to participate in their funeral procession. If no one had discussed this matter with them, then one should consider: if they were in a country where monotheists and callers to monotheism exist, and there are means to learn about monotheism, then it is highly probable that the proof has been established against them, and thus, one should not participate in their funeral procession. Otherwise, one may participate.