Stupid lawyer thing that bugged me: Montana recognizes sister state power of attorney. Even if it didn't, there's no way Jamie can act as state attorney general and as attorney for the ranch in the same transaction. Plus, since the POA was from John to Beth, if it's invalid it reverts to John, not Jamie. There was no possible situation where John is in the room and Jamie could have had the authority to say, "as attorney for the ranch, I agree to sell."
They already addressed that conflict of interest in a previous episode. They just sort of forgot about it for this one.