A NY Times "journalist" and an overzealous Dr. Rosenberg were the ones who focused all their attention on the guy. If they had mentioned any other names, the press would have been out there showing the other people of interest getting the workover/vetting, too. But with one named guy and 29 others or so, the press was naturally only going to report on the one it had leads on.
As for how much anthrax is out there that didn't get opened by a curious Egyptian cat, well.... Iraq had quite a bit and they had to put it somewhere we haven't yet looked...