That would be a strange route to get from Denver to Williston. Maybe you are in the wrong thread?
Miles City isn’t out of the way of Denver to Williston. I went that way a few times with my parents when we were heading up there instead of taking 85 the whole way. In fact, if Tesla builds a supercharger in Douglas then going up via 25 to 59 to 94 to 16 through Gillette and Broadus is quite convenient with a stop in Miles City.