Achieved in Chapter 3, you lose during the fight against Baby Giulia, she takes control over Matt and makes him kill everyone; and himself...

You don't have all of the items for the end of Chapter 3, making you stuck in Theme Park forever, but the group ended up seeming to get teleported somewhere, separating them. Matt gets teleported to a long hallway, with hallow in heart, he moved forward, "(And the weight of the steps... Came the weight of my regrets...)" suddenly, a tall Mario - possibly an animatronic - approaches behind him. "You surely were... An interesting experiment..."