I have a call recording where my girlfriend says to her girl, friend, " -where you going? " -Room 105 (background woman voice) -Oh 105 at the girls room. you wanna go first or I go first?"

This was recorded in a call, later on we spoke and she said she meant go first to take a bath, today she says 105 is boys room spontanously when I ask her, and I send her the recording where she says she's sure it's 'Oh the girls room'

She then replied " I was confused when I said that "

​

All this in a school trip while they're back at the hotel. I guess it's a gangbang that happened. How should I go on from here, as I presume she clearly lied to me and what to do/tell her? Or if you deem necessary, how to break up? Ghost? Hard next or soft next and plate some other girls?