I don't think he's dead or else sherdog or other websites would have probably said something about it. Plus the anti MMA bastards would use it to there advantage.
But ya alot of injurys make it hard for fighters to come back, maybe he's just turned into a trainer, who knows.
What is it that is going to be on your mind when you're on your death bed? Will it be the tedious years of 9 to 5, or the memory of some great acheivement. Maybe a moment you stood in glory to the applause of millions.