On the contrary...
At this point, I believe evidence is needed to prove Osama is alive. Such evidence would be so simple to provide (a photo of Osama with today's paper), that the lack of it is suspicious in itself.
Baghdad Bob and Al Jazeera have shown the tendency for some in the Arab world to live in a fantasy and cheerfully lie to support it. The idea of Osama still leading his people is such a fantasy.