This page of our guide to Life is Strange True Colors contains a description of Part 4 of Episode 4. You'll meet Jed and find out who's behind all the bad events.
When you get back from the station, you'll see a letter from Jed - he wants to meet you.
You will have a minute to yourself, though. You can look around the apartment, look at some objects and go to the roof. You need to change the outfit before you go meet Jed, though. In this case, you have no choice, Alex will choose the outfit on her own.
When you've done everything you want, you can go to the door.
You'll meet Jed downstairs. He'll be happy to talk to you. He's curious about what you found out about your brother's death and what happened when you were at the police station.
You can tell him the truth, play coy or just have a drink. Alex trusts him, and she'll be happy to tell him what she found out.
Jed will take you to a place where you will learn the truth. You can't skip this sequence. It has nothing to do with the choices or relationships in the game.