Bundle automatically names cluster elements for some references but not to a VI.
Indeed, but that has nothing to do with the Bundle primitive, which simply takes the wire names.
In this case, the wire coming from the static VI reference has no name.
The more technically correct idea would be: "The Static VI Reference node should name its output wire the same as its label (which is normally the qualified name of the referenced VI)".
In your case, it should output a strictly-typed VI reference named "Editor.vi".
Then the Bundle would use the wire name as for any other wire type.
Then it's too bad that explicitly setting the Label of the wire does not name the element. Wire Labels appear to default to blank (see Vertical Softkeys wire) and changing one has no effect on the bundle element (see "wire Label").