You're right, but the blame does lie with multiple people too. Yeah, his only chance of saving his skin is if other's responsibility somehow diminishes his own culpability, but he will soon find out this is not a zero-sum game.
But shouting "fire!" In a crowded theater isn't free speech and will get you a jail sentence if it creates a disaster. Infowars (and Alex Jones specifically), and other organisations (they identify libertarian and mainstream conservative content plus youtube algorithm) also need to be held to account for inflammatory speech that encourages violence; provided that it can be demonstrated that they're pushing dangerous misinformation. Especially if they are making money doing it.
I won't hold my breath waiting to see that happen though.