I don't think anything happened. I feel like his priority would have been finding Mute in case he came and found him first, and showing the monitor to Rudd was more just highlighting that he was going to do something later. Also, the girl didn't exactly seem like anything had happened to her (though I realise she might not have realised what had happened at that age, or just been in shock). It's a bit ambiguous though.
But... the way I saw it, she *is* left with the paedo. I mean, I presumed very bad things happened to her after he let Rudd see the screen and then went and took her from the room.
Because this way, 'Barry Mute' doesn't kill the girl's biological father, but rescues her from the paedo, and Rudd pays for killing the girl's mother by thinking his daughter (the only thing he actually cares about) is left with the paedo.
Can anyone justify the paedo aspect?
Like it was handled terribly but I can't even think what the narrative justification was.
And why did he and Barry Mute have the final confrontation on the bridge instead of Rudd and Mute?
Did they not? Did I imagine a bleaker plot point than actually happened?