The event you refer to might have been the cause of mass extinction at the end of the Permian period, but only because the magmatic flow cooked enough carbonace

The event you refer to might have been the cause of mass extinction at the end of the Permian period, but only because the magmatic flow cooked enough carbonaceous material to raise the temperature of the Earth significantly due to increased concentrations of carbon dioxide in the atmosphere; I would call this a secondary effect related to magmatic combustion and not an aerosol-heavy event associated with a silicic eruption.