That seems to be a different mechanism to get Adobe Stock templates into your libraries. All of those libraries exist local on your computer.
on the Mac in the user library > Application Support > Adobe > Creative Cloud Libraries > LIBS
on Windows it must be something similar in the Roaming folder or whatnot.
There may be a couple of even more folders in that folder. They contain the assets and manifest files.
The templates don't exist as source files, but are linked from Adobe Stock via the manifest files.
Maybe you can hack those manifest files in order to sneak your templates into them, but I doubt that.
Probably it will be easier to just post a feature request on http://illustrator.uservoice.com