Looks like I have solved the Cluster joining issue. Thanks @stephdl for the journalctl tip. I ran it on both server then attempted to join the second to the cluster again. Looks like there was a DNS issue and ns8 was searching for full FQDN of the host instead of the IP. I added the host in /etc/hosts. After the the node joined to the cluster fine.
I still have very slow GUI loading issue as shown in the following screenshot. But At least i was able to join to the cluster.
Not sure what that really meant. Probably something I dont want to get into.
This was not to meant to show the prowess of my virtual environment, but to convey that all other VMs were working without any IO issue or anything related to the Hypervisor itself. The issue was most likely isolated in the NS8 deployment itself as it turned out to be the case in this instances. Even though it was my DNS causing the issue, still the issue was inside the NS8 itself and not outside.
This cluster joining issue can be called Closed. Bottom line, NS8 uses FQDN of host to reach each other. So either use of DNS entry or coded in the /etc/hosts must be done.