I still have the iOS app installed, and it still seems to work. I recall seeing an update available a few months ago. I read a couple reviews within the App Store stating that the update was basically designed to disable the app, so I opted not to install it. Looking now, I see the FCC test app is no longer in my list of pending app updates (which makes sense if it's been pulled completely).
That point seems to emphasize the other questions in the article. Especially, if these numbers are updating, where are they coming from? The apps don't seem to be available in the standard places, so how could statistics (other than "zero", I guess) be gathered about them?
EDIT: it seems conceivable that whoever decided to pull the app, decided not to spend the political capital required to pull its statistics.