No it is not true. I think what he is referring to is
a mock documentary that was on the discovery channel a few
weeks ago. It was a show that was done to make it look
like they had discovered dragon bones in an arctic cave.
The show went on with the life of the dragons, how they
were able to produce fire, what they ate, etc.
they showed how the scientists had pieced together the bones and what the dragons would look like. they even recreated scenes of man hunting the dragons.
It was a good show, but alas it was just fictional.
If I remember right Patrick Stewart did the voice over
for the show.
I think this is what your friend saw
http://familyscreenscene.allinfoabout.com/tv/dragons.html
you might want to send him to the link so that he
realizes that it was just a fake show and not real.