If he was doping, I would think the odds are he was not the only one on his team that was. Maybe that played into the team's decision to withdraw - they didn't want any of their other riders to get caught.
Oh, they'll get caught. They just won't be in France to be manhandled by the French police. Ricco's test was from Stage 4, so the tests are about a week behind. I have no doubt there will be more positives.