You do know that this is unique because of how Montana Law is written.
Of all the US jurisdictions, states and territories there are only 6 US jurisdictions, Colorado, Iowa, Michigan, Montana, New York, Rhode Island, that have similar language. The language prescribes that if a mandatory reporter fails to report, then they can be held civilly liable for proximate damage by not reporting the matter. In all other states the only penalty that is prescribed is criminal. Either prison time or a fine. In those states, state courts have ruled that if the state legislature only prescribes a criminal liability for the violation of a law, then a person doesn't have the right to bring a private cause of action against the person. In other words, in the other jurisdictions, because the law doesn't say you can sue the mandatory reporter, you cannot sue them.