If Ethan is curious about everything and wants Nat to be a slut, I don't think there is a Jenna confrontation. You see her early, Ethan can be intrigued, Nat thinks it is interesting, Jenna sends some text, has lunch with Nat and wishes she had a job like Jenna, then the swinging party. The only confrontation is with the kid who wanted to creampie Nat. In order to get a Jenna confrontation with Ethan, he needs to be shocked or not be into Nat screwing other men before Jenna comes over to "persuade him".