As expected, though one never knows with the tribal court jurisdiction cases, the Supreme Court denied cert in API v. Sac and Fox (order list here).
API was a non-Indian-owned business hired by a tribal group (or individual) to enter into a tribal governmental office to retrieve documents and perform other security-related tasks. The tribal court held it had jurisdiction under Montana 2 to adjudicate contract and tort claims relating to that activity. There probably isn’t a better fact pattern for a Montana 2 “political integrity” exception to Montana’s general rule.
Turtle Talk 
That’s awesome! But…it would have been nice to get a Supreme Court affirmation on tribal sovereignty and tribal court jurisdiction over non-Indian corporations. Especially since they have been consistently eroding both of those illegally via their own jurisprudence.