I'm 100% sure none of casinos where the location is infected by Corona Virus is still operating, authorities know that contact among gamblers cannot be restricted, gambling casinos are the first to close when the virus hit the location they are on the category of concerts, festivals and meetings.
Everything is closed, in most countries. But there a chance that in some casinos, like in some cafe and restaurants the same rules: 3 meters between people, and cleaning every hour. Of course i highly doubt for this. Maybe someone knows what in Monaco?