As for this whole Riis thing, let's just conclude he's a very, very stubborn character.
In 1999 a couple of Danish journalists made several tv programs detailing doping in international cycling. Back in 1995 one of them had worked as a masseur for Gewiss-Ballan and had used that opportunity to collect trash left by the soigneur and to get other inside info like lists with riders' hematocrits on them.
What they showed where bags full of medicine including unlabelled vials that turned out to be EPO. The hematocrits lists showed that all the riders on the lists had normal levels that at later times where all in the fifties.
Later in the program they interviewed Riis, who in the face of all this denied any involvement in doping and said "those are not my numbers" about the hematocrits. Just like Lance can say about the positive 99 urine samples, Riis could say this...
Now this is back in '99 and he didn't come clean until 07, so there no doubt that no amount of evidence would have made him come out.
Throughout the years since then there has been the occasional "did you dope" question, which he consistently denied. Even in the spring of 07, mere months before coming clean, he was directly asked in an interview if he could deny doping, which he did.
He only came out as everybody else (apart from Ullrich) had come out from Telekom. That whole thing by the way was started by another Danish Rider, Brian Holm, who is Director Sportif on Columbia now, and was quickly followed by the handful of German riders.
Then, and only then, did Bjarne come clean. Obviously he has a cycling team to protect, so he couldn't risk keeping this personal stuff interfering and endangering the team. But secondly he did not under any circumstance want to put his old teammates in the same position where they had to defend themselves yet again, so he would never be the first man to admit doping. That's omerta for you...