Thanks for asking. In short, the source code is still not available.
Yes, it is true that some time ago in a thread on the Unity forum the GameFlow author wrote: "If I ever decide to discontinue the development of GameFlow for a reason different to an acquisition, I will disclose the source code" .
And it is also true that the product page was modified just recently to announce that we are no longer maintaining the tool, but notice that we also removed the screenshot refered to the source code question (where the "opensource" term was used explicitly).
The reason for removing that screenshot is that we would like to have a "grace period" (maybe some weeks from here) just to reconsider our decisions on both the maintainance and the opensourcing questions. The moment we have a final decision we will announce it here, so please stay tuned.