Essentially, what you need is something like a UI Query that returns all of the VMs in the service so you can then build a view based on those inside of the service.  There is an example of this in my core community cartridge and attached is an image of what the definition of the query looks like to make it work.

Are you using a custom report to test your service, and does that custom report work with the VMWare service?

As Tom says, the trick is not in the service, it's in the report consuming the service. 

Try running a standard report, using your new service.  If that works, then it's the report spec.

And, no, you can't select the service from the dropdown on the VMWare Environment page,

that page has a bug which prevents it from using custom service definitions, even though they appear in the list.

You should be able to use any service in the VMware environment page if you mark it as being part of the VMware domain.  The only thing that the VMware environment page should care about is that it filters out any services with the name ESX or ResourcePool in it.

I've got about 60 different services I've created via service builder that all show up in the drop down list in VMware Environment.  You are on 6.6.1?  It should work with no issues.  If the service somehow has a name that is part of the query filter that could explain it.  That view has a filter on a slew of words.

Yes, FSMDynamicManagedComponent, service contains around 200 VMs, tests fine, and works great with the standard reports.  Wierd, I know.

The services show up on the dashboard dropdown list, they just don't display any data.

Perhaps that dashboard is limited in some other way.

Yep, you would think so, but no.

That's why, the DMC is technically a layer or two deeper than those queries/functions look.  If they are in the root of the service they should enumerate.

That's even stranger, it's not enumerating the contents of the service?  Are they in a Dynamic Managed Component?