Can I add the Ghosts to a 2-player game, or play them cooperatively?

Question

Accepted Answer

There is no official mode for either. The designer says adding the Ghosts to a 2-player game is not an official variant (it makes a longer, more complex game), and a cooperative mode is not being considered.

Dwellings of Eldervale

Can I add the Ghosts to a 2-player game, or play them cooperatively?