Luna and Radomus both have Malamar, Serra and Titania have Alolan Sandslash, Radomus and Adrienn have Gardevoir, Kiki and Samson have Lucario. Gym Leaders do repeat Pokemon, so Tyranitar isn't out of question.
The next leader could easily have lvl 94 mon in their team, since Amaria already had lvl 91.