You've got your own Visual Studio extension with custom CodeLens entries (because you used part I of this series), but now you find yourself needing to call code in the main extension host FROM the CodeLens Provider. How? Read on!
What this did, however, is gave us cause for figuring out if CodeLens is enabled in Visual Studio at all (our provider doesn't do much good if everything is disabled).
If you have your own Visual Studio extension, and you want to add your own custom CodeLens entries - I'm here to help, because I just (finally!) figured out how to do this (plus a few extras!)