There isn't a single deciding factor, is probably the longest chain quest in the game with many things to do in different updates. Easier thing to do is check the wonderful dundun's scene guide in the first post and follow the steps listed under Norman (Mom's friend): follow Ash's Mom after meeting Iris at the park, remember she was in a White BMW when visiting Ethan's house for the first time, go investigate the Wheel, contact Norman by Facebook, flirt with him when meeting in person, try to get inside the club when meeting him again and then either give him something to enjoy or blackmail him with telling his wife, an then when sleeping in Ethan's house call Norman in order to go to the club.