Suzuki went bankrupt. I think Mitsubishi would likely be held to a higher higher standard of care if they voluntarily left.
Of course, the arbitration agreements and the general weakening of consumer protections as SCOTUS and the Circuits move to the right probably makes this irrelevant. Massachusetts consumer protection law used to offer significant protection to car buyers, now due to SCOTUS, it offers almost none.
Mitsubishi would probably decide to just close up shop and tell aggreived owners to take a hike or hire a lawyer and file arbitration, which would likely cost more than the repairs sought.