Once again John states that the "Train Station is across the border in Wyoming in a county consisting of no people, no law enforcement, no judge and jury of your piers, and no one living within a hundred miles". This must be a fictional county, as all counties in Wyoming are inhabited, though some very sparsely. Dumping bodies across state lines in a county that has no, or even a very small, law enforcement does have its advantages, makes it harder for them to pursue a case if the bodies are found, a lot of small counties don't have the budget or personnel for major homicide cases. However the biggest downside to this is if the bodies can be tied to the same person(s), and it can be proven the people were killed in another state and their bodies brought across state lines for disposal then that would make the murders a federal case under the jurisdiction of the FBI, and the Duttons would be facing trial in a federal court.
In Roy Rogers final movie, Mackintosh and TJ (1975), the name of the ranch where they worked for Jim Webster was the "6666". This was also a cattle ranch and located in Texas.
After Jamie announces impeachment proceedings John, the Senator, and the Press Secretary are watching a local newscast about a possible connection to the wolf killings and the Yellowstone Ranch. These are two body blows to the Duttons. John Dutton can be seen wearing a United States flag lapel pin that is upside down. An upside down U.S. flag is a signal of emergency or distress.
The "Train Station" is apparently located over Montana's border with Wyoming.
When Monica asks John where the cattle are going he says "we leased some ground in the panhandle of Texas". In episode 7 he says the cattle are going to eastern Colorado, north of the panhandle of Texas.