I've raised a bug here - https://windowsserver.uservoice.com/forums/295071-management-tools/suggestions/37729852--bug-can-t-c...
I've installed Windows Admin Center with high availability following https://docs.microsoft.com/en-us/windows-server/manage/windows-admin-center/deploy/high-availability.
I can connect to nodes in the cluster fine through WAC, however when I try to add the cluster it says it can't find the name.
If I click on one of the nodes it gives the FQDN of the cluster, I click it and it adds it as a connection but when I try to access it, it complains that WINRM couldn't not process the operation.
I've tried it with two different clusters on our network.
I've checked and the cluster IP that is on a node is showing as listening on that IP when running winrm e winrm/config/listener in PowerShell - so that doesn't seem to be the issue.