In retrospect a lot of what Petey said now makes sense

iMark and oMark, during their discussion, try to come to terms with what a reintegrated Mark would be. I think innie mark got it right and we have previous Petey dialogue for that.

“I am your best friend. You are my very good friend”

Petey is already fairly reintegrated. His innie lived only a fraction of his life. For his perspective, he is Marks best friend but his best friend (for outie Petey) is his daughter. After reintegrating, albeit partially, his daughter is more important than Mark and outie Petey is more present than innie Petey.

He was very much a badass for going through it and having enough compassion for his innie and everyone else he met there, including people he never met but discovered that existed somewhere and could never leave.