That was also my first thought but didn’t want to voice it since it just seems to darn unlikely.
I guess it wouldn’t surprise any of us if it turned out to be some random new character or some other plot element that had no previous buildup. Then again, stranger things have happened. We did get a few long unanswered questioned surprisingly answered in 5B, for example. The only other thing I could think of is that maybe Prince Thomas was sent there, after he mysteriously vanished. I’m not sure how that’d tie-in with the present day LUS storyline, though, considering that Thomas eventually ended up in Storybrooke and reunited with Ella back in Season 1.
Yeah…we never did learn where Prince Thomas was sent did we? If his actor returns, I’m sure that’s it for sure!
"If you go as far as you can see...you will then see enough to go even further." - Finn Balor