I think that what they are trying to say is that the probability is so low that it suggests manipulation. e.g. In a high stakes poker game, I was dealt an 8 high straight flush, so I went all in. On the very same hand, someone else was dealt a 10 high straight flush. I think they were cheating. It is statistically impossible for that to happen.
No one would say the above situation was "mathematically impossible", because that term is reserved for things that are literally impossible, such as having a right triangle that has sides with length 2, 3, and 4.
In the poker game example, that isn't actually impossible. In fact, the probability can be calculated precisely, and it is not zero, but I can see people using the phrase "statistically impossible" to describe it.
Of course, applying that to Navarro's idiotic report is balderdash. They don't have any statistics or probability that has any basis in reality at all. They're making stuff up. They're lying, and hoping their followers don't have enough knowledge or interest to see through it. Based on previous experience, that's a safe bet. I just don't know how big of a group the "followers" are. 10% of the country? 40%? I don't know. Too many? Certainly.
