Um, if 'wrang out' is - as you stated - an Oklahoma regional/local expression it is therefore, by YOUR definition, not a national expression and thus may not be applicable to Wyoming.
You don't have to be an expert to make that conclusion.
Right, no one has to be an expert when it comes to jumping to conclusions! How many Western short storys and novels have you read which were written by people who live or have lived in the US states in which the fictional Jack Twist lived and through which he travelled? Have you ever read any of Robert Conley's books? He is an awarded Western fiction writer and also writes Cherokee historical fiction. In his Cherokee "Real People" historical novel series, he has the Cherokee Nation of Oklahoma's approval for those stories. Part of what is in his "Real People" series comes for oral history of the Cherokees and was not printed in a book before. But, while he does not cite the source of the oral history, I have heard the same, or almost the, same oral history.
A little off topic here, have you ever read the Western Novel, "Native," by William Heywood Henderson? That story also takes place in Wyoming. And it is about gay cowboys and homophobia, too.