@Peter_Clark pfsense and smart switches with vlans configured could have some extra’s also local i think.
But he did write before also regular router no succes , so i think problem is or on client , or on webmin box some firewall, not allowing those ports , is the most simple explanation for me. I could be wrong though. 
U did he acces on ip?
If not but on via dns/ domain name, then it could be over outbound traffic, so isn’t it local in real.
Then he have to set or that port forward in router / firewall , or make that domain local accesable in for example host file or some dns.
EDit i see screenprint on local ip, i hope same network segment. then forget my last few lines above here
But still for local things i use myself a hosts file on those clients to not have to do over ip adresses.
so:
10.50.0.67 hostenname
10.50.0.67 domainname