Newly installed agent does not discover all the targets on a host

 I've installed a new 12c Release 2 agent on two hosts in RAC one-node cluster.

The cluster is discovered properly though Setup |  Add Targets Manually | Add Non-Host Targets Using Guided Process (Also Adds Related Targets)

However, the databases and listeners in the cluster can not be discovered using the same method.  

We've done this successfully dozens of times on other hosts, but sometimes we need to give the agent a little help.  So I log into the host and run emctl config agent addinternaltargets.

Follow that with emctl config agent listtargets from the same agent session and -- hold it -- where are my database targets?