I'd like an answer to this question myself.
Besides, people are prosecuted and sent to prison all the time based on just an eyewitnesses testimony, or an inference from circumstantial evidence. In fact, very few convictions have definitive red-handed smoking gun proof. Usually it's only famous people who get that generous standard -- like OJ and Clinton. So VA Advogado you may want to read up on how the criminal justice system really works. And no I'm not going to post proof that it works the way it does. Do your own research.
As for this case, the book and information about what the FBI ignored are there for anyone to read if they are truly curious or skeptical and want to check into it the connections. But this is an old case where publicly known leads were dismissed for political reasons, left to grow cold, and evidence was withheld by the FBI. So don't expect a miracle finish.
Just as we can't ever prove Iraq is involved in terrorism enough to satisfy people who demand concrete proof, even when Israel produces hard documents about Arafat's involvement in terror, people still deny that. After all, people can always say witnesses are unreliable or that's "just a piece of paper." R Kelly and his defenders will even say that a video tape doesn't prove anything.
At least this guy is doing research rather being an intellectually lazy complainer. He doesn't have to prove anything to anyone. It's simply an ongoing research project posted for the curious. The fact is he correctly predicted that Padilla would be connected to Benevolence International if he really was a potential JD #2. That just happened. And he made this prediction after he saw the photo comparison and saw that Nichols was said to have met with a BI contact in the Phillipines.