Updating existing KML through a hyperlink in description - kml

Question

I am using Google Earth 5.0 Client. I would like to update a KML file (loaded by a NetworkLink) by clicking on a hyperlink in the description/balloonStyle tag of one of its placemarks.
Here is an example:
A.kml
<?xml version="1.0" encoding="UTF-8"?>
<kml>
<NetworkLink>
<Link>
<href>http://www.example.com/B.kml</href>
</Link>
</NetworkLink>
</kml>
B.kml
<?xml version="1.0" encoding="UTF-8"?>
<kml>
<Document>
<Folder id="entities">
<Folder id="en1_folder">
<Placemark id = "en1_point">
<description>
<a href="http://www.example.com/getConnections.php?en=id1"
type="application/vnd.google-earth.kml+xml"> Get connections </a>
</description>
<Point>
<coordinates>...</coordinates>
</Point>
</Placemark>
</Folder>
There are about 500 such folders, each with its corresponding en# point
containing a description hyperlink.
</Folder>
</Document>
</kml>
If a user clicks on a hyperlink, I want to generate a set of LineStrings connecting that point to one or more other points.
For example, getConnections.php?en=id1 could generate a response like this:
<?xml version="1.0" encoding="UTF-8"?>
<kml>
<Update targetHref="http://www.example.com/B.kml">
<Change>
<Folder targetId="en1_folder">
<Placemark id="en1_connections">
<LineString>
<Coordinates>
(en1_coords), (en5_coords), (en7_coords)
</Coordinates>
</LineString>
</Placemark>
</Folder>
</Change>
</Update>
</kml>
This doesn't work in GE 5.0. I understand that Update is a child of NetworkLinkControl which in turn must be requested by a NetworkLink from the same domain as the KML that contains it.
I know there are several workarounds using one or more NetworkLinks, however I am curious to know if there still exists a way to directly update the same KML file by clicking on the description hyperlink.
Any thoughts appreciated.
Thanks,
Max