He was an independent contractor so he would have been entitled to workers compensation (if he carried his own or he worked for another) as well as a third party lawsuit against the property owner even if it was the employer. (credit is given to the WC carrier in the event of a third party recovery).
He offered comedy, non-political comedy and satire. He made fun of everyone, conservative or liberal, but was able to pull it off without being cruel and disrespectful. When you tune in you got comedy, not non-stop political commentary and diatribe.
Johnny had more artful comedic ability and charisma in his pinky finger than today's so-called late night comedy show hosts have in their entire body. They could only aspire to have a tenth of his talent....that would be a 100 times more than they have now.