Dr. Boom and Hagatha are already heroes. Rafaam obviously got a non-Hero legendary, so it’s fair to rule him out. Madame Lazul is getting a Hero portrait, which makes me doubt they’d also give her the Hero card. I’m calling Togwaggle as the new Rogue Hero card due to the top hat. Top hats are always worn by nefarious characters in WoW and HS so it suits the class.
Any other guesses?