This happened. Not sure how because there were way too many pieces on the board. Day 30+. I tried to take the king but my piece acted like the square was empty. So maybe the piece was supposed to be removed but instead just remained on the board inactive
I also found an easy way to get souls quickly. Pick as many tarot cards on your starting pieces as possible (emperor helps here), beat the first island, move all your pieces away from your "ship", then embarking will destroy all pieces and cards giving you lots of souls. I get 50+ souls with 5 pieces + cards. It's way too powerful.