The VLC media player worked great, is free, with an easy to use gui interface. the player is actually both the client and server. So any Windows box I put it on could be a server or a client. but without igmp setup properly I noticed it appeared to be multicasting as I had intended, but was actually broadcasting. Had to bring up wireshark to see that even when I turned off the client, the packets continued to be recieved on the port.
I am able to see rx_multicast increase from Ethtool's output "ethtool -S eth2 | grep multicast" on Server 3. It shows same number of multicast as Server 2. Does it mean that multicast packets have actually been mirrored to Server 3?
However, I still don't get any multicast traffic from tcpdump. Any ideas?