Just because it wasn't shown to the public doesn't mean a thing and gives no way to dispute it [atleast as an industry outsider].
Wouldn't they have had a better demo though? It was pretty unimpressive, and didn't really prove that Free-sync is capable of the same things as G-sync at all. The eDP standard they used has been available since 2009 and that demo was the best they could do after "years of research"?
Even now, it's still a year until we can expect the first hardware even though they've supposedly also been working with manufacturers for a while.
Meh, I don't buy it. Makes a lot more sense that Free-sync is just something they whipped together as a response to G-sync. And it's working too, people are writing G-sync off, even though we barely know anything about Free-sync at all.
Marketing spin aside, I hope it succeeds. The faster this technology becomes mainstream, the better.