Could it be possible to have a dungeon that is meant to be scary or creepy of some kind?

Music is ambiance, not a song.

Everyone can only see a few feet in front of them. Force the group to stay together otherwise the encroaching darkness pulls them into the dark and party member gets killed by a monster that can't be seen. Don't give a timer on how long you can be apart to add to the scariness.

Have lots of puzzle that that you quickly split up or something. Maybe have sacrifice a party member to move one temporarily?

Just something dark and creepy. Imply things that maybe you want us to think, such as maybe Louisoix grandkids really don't get along.

If the game is supposed to be a theme-park, where are the haunted houses?