Few things I noted from Episode 14:
Elaine while sitting on top of the MC on the beach says :
".... I just wanted to prove that when it comes to MIND GAMES, you'd NEVER WIN against me."
Jolina is a question mark after this update. She knows a lot about Monica, Jenna, and Katie more than MC expected her to, plus her reaction when MC shows his father's picture to her, raises a few yellow flags atleast.
My money now is on three, Zarah, Elaine, and Jolina. Zarah, for obvious reasons, she is the one that a lot of people don't like. Plus she is a wild one, can't trust that kind. Elaine, is either really as loving as Monica or she is one of the major players whose acting in front of MC is Oscar worthy. Her picture reveal to Jolina ain't clear, coincidence? I think not. Jolina, A big question mark, has her own secrets.
Don't know if Zarah is the Dogboy's bitch mother, don't remember much about her background. If she is not, then that's another addition we know nothing about and she maybe another suspect.