I view the house as us, “the main character” surviving. Our role in the House is the final girl/final boy. Sid and Nancy are the two who disrespect the graveyard and awaken the spirits. We are the nerdy friend dragged along who is open minded to spirits and respectful. I view the tunnel scene as a near death experience where we are almost dragged back into the graveyard to play for all eternity. Next, when you see Glowing Mother, she is granting us passage to escape with our lives. The final scare is then a tribute to the classic jumpscare at the end of most horror movies and a way of saying “get out and never return”.
However, this is just my interpretation and the way I view it.