Hi,
In Usagemeter to meter vRealize Operations Manager, you must add vCenter Server which is managed by the vRealize Operations Manager.
vRealize Operations Manager will be auto discovered, once the respective vCenter Server is added into the Usagemeter .
After vRealize Operations Manager got discovered in the Usagemeter, Please accept the certificate and type in username/password using "Edit" button.
Hope, this helps you.
Thanks,
Vinayaga.