Internecine warfare is the most likely scenario.
Multiple factions within Iran are at odds with each other.
I doubt that highly. The West is moving against a nuclear Iran and the Iranian regime, which has boasted of its invincibility, has to pretend that nothing is happening because it cannot effectively retaliate or admit that it is not in control.
The move against the Saudis was stupid and effectively removed all regional objections to a countermove against Iran.