This smells like a nefarious scheme anyway you see it.
While the fact that this wasn't a simple case of photoshop-effect clusterfuck can be easily proven in court, only needing to get the artist up there explaining his process and maybe showing a few WIP images here and there, Baio did say that defending his claim of fair use was waaaaaaaay too expensive. And apparently Maisel is described here as "an aggressive copyright defender", so he must have known how expensive defending the case actually was.
So, determining that Baio was better off just handing a small amount of cash over and getting it over with, he went into full aggressive mode to get the quick buck. He might have not cared about how much Baio would be screwed because of this move, because most likely Maisel was actually a little ticked off that no one asked for his permission.
It's pretty obvious, really.