A googolplex is ten to the googolth power. That's a googol/100 factors of a googol. So we can keep doing this, gradually - very gradually - diminishing the degree of discomfort, and multiplying by a factor of a googol each time, until we choose between a googolplex people getting a dust speck in their eye, and a googolplex/googol people getting two dust specks in their eye.

Maybe the strange notation has me confused, but I don't see the contradiction here. Consider sneezes. One human sneezing N times in a row, where N>2, seems at least super-exponentially worse than N humans each sneezing once (assuming that no noticeable consequences for any of this last beyond the day). In fact, if we all sneeze simultaneously that would be pretty cool.

This next part doesn't directly address the original question. But if 3^^^3 humans know that by getting a dust speck in their eye they helped save someone from torture, the vast majority would likely feel happy about this and we wind up with a mountain of increased utility from Dust Specks relative to No Pain. Whereas an average-human torture victim who learns that the torture served to prevent dust specks might try to kill you bare-handed.