Probably a dog/wolf hybrid. It has strange fur. Teeth look more like dog.
https://www.bozemandailychronicle.com/news/mystery-monster-returns-home-after-years/article_461c6958-ea1e-5f57-bee9-a3c11b0a18a6.html
Above is a link to an article I recall from years ago. Looks to be a similar creature. The guy’s grandfather killed it in Montana 121 years ago.