You guys ever notice that characters from other teams are often included in the endings.
Ash's ending has Shen, DuoLon and Oswald.
Joe / Terry / Andy's ending has Mary, Mai and some random transvestite.
Kim / Hwa / Raiden's ending has Chang and Choi.
We know that Billy might be in the game, and Mary was on his team a set of times. Does that mean that Chang, Choi, Oswald, and anybody else featured in the ending could make it into this game? It's a stretch to say that it's a definite yes, but there's a chance those characters could show.