unable to add to vcenter

[Hr46ph]

vcenter removed the esx server from the cluster and I am unable to add it back.

I keep getting:
Authenticity of the host's SSL certificate is not verified.

I tested DNS lookups and reverse lookups from the vcenter and that just works fine.
I changed the certificate mode to custom and tried thumbprint as well, neither works.
I added the certificate chain for lets encrypt to the certificate manager, didnt help either.

I had to remove the app and revert to self signed from the vmware ca.

Does this sound familiar? I read the wiki troubleshooting and searched issues and discussions but couldn't find anything related.

The error I receive is plenty to be found all over the net, but the solutions don't seem to work.

If we can't solve this, you might want to add a big fat warning somewhere because once a server is removed, all its settings are removed as well (think monitoring, alerts, all host specific settings basically are gone.