I don't want to sound rude, but is this really a good idea? Are you sure this is safe?

Not the process itself...don't get me wrong rowdy but if you have to ask where to get the viruses, it reduces my confidence in your abilities to properly manage this hostile environment you've described.

How do you plan to infect the virtual systems, and not the host itself? How are you going to keep the virtual systems from infecting other devices on your network? How are you going to ensure the video data of these activities is not infected when transfered for production and preparation for use in training?