I have no reason to believe it's not rigged. Unless you actually SEE the whole process you have no proof.
I understand they are audited by reputable companies and so forth. Sure they audit the process but do they issue an opinion on it?
If they don't issue an opinion then they haven't put their reputation on the line. Even if they issued an opinion you would have to get the details to show that the opinion is based on the same outcome you are looking for.
I have no doubt that it is rigged. As a business, could you REALLY leave some of these massive factors that could sink an entire team up to the luck? I think not.