I was afraid that graphic and quote might send the wrong impression.
And I almost posted a clarification. I guess I really should have. But better late than never.
The funeral that Quentin witnesses is indeed Angelique's - and the skeleton that is discovered behind the brick wall is Charles'. However,[spoiler]the coffin that was buried during Angelique's funeral was indeed empty. Angelique's real coffin was actually locked away in a room in the basement of Collinwood - and Charles was thrown into the same room and imprisoned by Gabriel after the entrance to the room was bricked up. That's the reason that after Gabriel threw Charles into the room he told him that he would have Angelique for eternity.
(An upcoming quote (the 19th's) from the seance scene will actually explain that after Angelique's and Charles' bodies are found, they're buried in holy ground.)[/spoiler]