I have a 2x Lenovo servers that connected to Lenovo data-storage solution via Fiber-Channel. Both servers are exactly the same and running Windows Server 2016 Datacenter Edition. All required server roles/features added. Servers are NOT connected to domain controller (workgroup connected). They both connected to same Mikrotik router and located in same subnet/mask etc. Network set to Private and Firewall disabled on both of them. They both have same DNS-suffix (while I still don't understand what is it) and same DNS if check via "nslookup".
Servers can easily ping each other, but when I try to create a cluster - it's impossible to add another node into it. This issues presents no matter from what server I try to create a cluster.
A bit of visuals for better understanding:




What else did I miss on my way to create a cluster?
P.s. I was following this guide to create a workgroup-joined cluster