You know…maybe I’m warming up to the Frankenstein theory a bit…
If Regina used the magic portals in the hat to pull Dr. Frankenstein out of his world in hopes that he could bring Daniel back to life for her- I could buy that. It would give a reason for such an out of place character to be present. I’m not entirely on board, but at least I found a way that the theory would make sense!
That was my major sticking point too, I just couldn’t figure out how they could weave him into the story. But it’d make perfect sense if Regina enlists him in a desperate attempt to bring back Daniel.