Should Crown Tundra count?

I decided to do a nuzlocke of Pokémon Sword, where I will attempt a series of nuzlockes to use every Pokémon in the game (I could extend it to Shield as well, but I need the DLC for that).

However, I ran into a problem. I don't know whether or not to include the Crown Tundra. This is because of the Peony fight which has you face his (I believe) Level 70 Aggron. What should I do? Should Crown Tundra count or no?