Why I think Micah is definitely the rat

A lot of people are skeptical about Micah being the rat, some people say John or Abagail are the rats. But in my opinion Micah is definitely the rat. A lot of people being up how agent Milton could have lied to Arthur in the van horn building before he got shot to separate the gang but I don’t see why he would do that, for all Milton knew he was gonna shoot Arthur and ship Abagail and Sadie off. If someone has a theory on why Milton would tell Arthur Micah is a rat and sabotage the game I’d love to hear it. Another reason is because Micah only denies being the rat when in front of other people, on the mountain when Arthur and Micah are fighting and Arthur says that’s Micah’s a rat, Micah only says He’s a survivor, perhaps hinting towards him snitching to survive the fall of the gang. I’m open to rebuttals in the comments