The clue to open this door is found on the note sitting on the table you briefly see before the camera moves to the coverage photos area.
Look at trading card No. 26 [Polly Oxford]
Look at Coverage photo No. 2 Nature #3
Watch the video no. 35 [Epilogue] on the TV
Play song #14 [Miss Stillettos Heels Full Version] on the Jukebox
A chime will sounds indicating the door is unlocked and go inside. Zach will be inside the white room once again. Follow the doors with the glowing white bush until you reach the room with York. Talk to York and he will give you Trading Card No. 65 SWERY.
If you go back into the room Emily wearing her black cocktail dress has joined York. Neither will speak to you but if you talk with them a short moment of them smiling and staring at Zach will play.