Like actually unless Beartic has bright powder it’s impossible. Battle
I think the Beartic had Snow Cloak as its Ability- increasing its Evasion by 20% during Snow (https://pokemondb.net/ability/snow-cloak). Since Alolan Ninetales set up Snow using Snow Warning, I'm guessing that's how it managed to dodge. Sorry if this answer is a bit hasty, but I hope it helps!
