Question: Yukon has a gun - why he didn't just shoot the snow creature at the cave?
Answer: Plot wise, if the snow creature had been killed, it would have ruined the happy ending. Yukon has a kind nature, and he probably wouldn't kill anything.
I'm not sure about that. He lured the snow monster to the water and watched it sink without knowing for sure it would resurface, then later to the edge of a cliff where he, along with his dog team, pushed the creature off. Yes, he said, "bumbles bounce," but it was still a violent act.
Answer: It's a kid's show, not Game of Thrones.