While looking through a list of un-dumped MAME titles, my eyes caught onto this unauthoritised pseudo-sequel to Ms. Pac-Man called Ms. Pac-Man Twin. It was created by a company known as "Susilu" and it allows two players to play the game simultaneously, with the second player operating a green-colored Ms. Pac-Man.
As opposed to the millions of other two-player Pac-Man games (such as Tengen's Ms. Pac-Man or Pac-Man Arrangement), there are two layers of pellets that have to be cleared from the maze; a red layer and a green layer. These layers can only be removed by the Ms. Pac-Man that matches the color of the layer (Power Pellets are universal, they can be eaten by either player and don't exist on a layer). Once both layers are gone, the players can advance.
So rather than giving you low-res distorted arcade screenshots, I went and made my own recreations, which includes layouts of the other three mazes.
Update: Here's V2 of the mazes, with a palette that replicates the original screens more closely.