Just to add to this, a Prigozhin government would likely be far worse for Ukraine. While Putin had few qualms brutalizing civilians and committing war crimes Prigozhin has none. He's a ruthless, murderous thug. The best outcome would be that he is defeated by the Russian military but that they have to withdraw troops from Ukraine, allowing the Ukrainians to seize the initiative with their offensive. The worst outcomes don't bear thinking about.