hosted-engine --add-console-password
Enter password:
[root@corp-ovirt01 ~]# virsh -r vncdisplay HostedEngine
error: Failed to get VNC port. Is this domain using VNC?

Yes. Sorry I forgot to copy that part. It didn't respond with a connection string. I was prompted for a password and then tried.

Ok, so maybe you configured your hosted-engine VM for spice only.

In that case you can:

directly check spice port:
virsh -r dumpxml HostedEngine |grep -i tlsPort

Copy ca cert (/etc/pki/vdsm/libvirt-spice/ca-cert.pem) to your laptop.
Identify the subject of /etc/pki/vdsm/libvirt-spice/server-cert.pem with:
openssl x509 -in /etc/pki/vdsm/libvirt-spice/server-cert.pem -noout -subject

Add a console password with
hosted-engine --add-console-password

Connect over spice with something like:
remote-viewer --debug --spice-ca-file="/tmp/ca-cert.pem" --spice-host-subject="O=example.com, CN=host1.example.com"  spice://host1.example.com?tls-port=5900