I haven't actually read the book, but according to lexicanum, "It should be noted, however, that Alpharius's death is still considered suspect even by the Ultramarines, and he may still be at large."
I'm counting Alpha as alive.
Well, the thing is though space marines are also incredibly agile and have thousands of years of experience, and it seems like bolters are as effective/more effective than shuriken weapons. In Brothers of the Snake, a large Dark Eldar incursion gets routed by one marine. In Know No Fear, they mention a single marine standing against twelve Eldar- they admit it's an impressive fight, but still, 12v1...