How is he being too friendly, Phoenix is his best friend who has never wronged him. Cameras are out so I think it would be okay for them to have fun going all out against each other for the first time.
I think you pretty much got his character down perfectly. Idk if a lot of people here need to reread the beginning but this mentality/lifestyle is pretty much all he thinks he has going for him even if it negative. He's even bad at the only thing he's passionate about, so he's huffing mad copium...