While community-scoped VIs are only accessible from VIs in the same library and friends, they are still exported.
To see the complete list of exported members, use Get Exported File List.vi or open the library from the Getting Started Window.
Attempting to execute community-scoped VIs results in a runtime error. Here is an example using Open VI Reference.
The same error should appear in TestStand (otherwise it's a bug).
LabVIEW simply hides community-scoped members in Project Explorer for convenience. Looks like TestStand does not do that.