This Virtual Server is default cluster group. but there also other groups which is not virtual server (no VS name and Virtual IP address, just some physical resources and file shares)

It is against Microsoft best practice to put anything other then the Cluster name, Cluster IP and the Quorum drive in the default group

If there are no IP or network names in the other resource groups then that are not virtual servers.

To install DX into one of the 4 remaining groups you will need to assign a network name and IP to them. Do NOT install DX into the default cluster group