No. Mario has expressed some pretty disturbing views that totally disregard any norms of due process. For instance, he was furious that USATF let Coleman get off, even though it was clear that there was no basis in the rules for a suspension, and realistically he never should have been charged. I'm all for a tough approach to doping, but I don't think you get to make it up as you go along.
There's a massive difference between what Mario is saying and what Jenny Simpson said. Jenny said "she doesn't feel sorry for you" if people suspect you when you choose to associate with a shady program. I'm in total agreement there. But it's one thing to say that it's normal for people to have suspicions based on the company you keep. It's something else entirely to say that you should be punished by the sport's governing body because of the company you keep.
And keep in mind, there already is a pretty aggressive prohibited association rule, FOR PEOPLE WHO HAVE BEEN SUSPENDED. Mario seems to be advocating a rule where prohibited association runs through additional degrees of separation.
Now, maybe there could be a workable rule where an agent that has more than X number of athletes get popped has to serve a suspension. These kinds of strict liability rules in the law are usually applied where the individual is the "least cost avoider," i.e., the person who is in the best position to make sure that things go well. I'm not sure that an agent is in the "best" position to make sure that none of his athletes dope. Sure, an agent could ensure that they DO dope, but I think it would be very hard for an agent to prevent doping by his athletes.
Of course, all this speculation about what kind of rule we COULD write that would lead to agents like Rosa getting banned is beside the point. We don't have that rule now. So that really should be the only answer to Mario's question: You don't serve a suspension unless there's proof YOU broke the rules.