That's exactly what we're talking about breh.
There is zero reason for Prop to be out there holding Marlo's hand like that. Nor was there any reason to bring Marlo around Spiros. This is a guy that was notorious for being a lone wolf, interact with him at the co-op, that's it.
And Prop Joe's dumb ass was sitting there talking about

"bu bu but....I treated you like a son". So nah, in his mind they were becoming friends. Which again, is completely out of character for someone as savvy as Prop Joe.
Fred.