Do you really not see why it is so "hard for folks to understand" why someone in Paterno's position and authority didn't follow up? Let me put my question in a slightly different way: What if it was Paterno's own son in that locker room - do you imagine for a nanosecond that he would have simply passed it on and washed his hands of the matter - because he didn't "see anything"?
Of course not. He would have seen to it that the matter was thoroughly investigated and that Sandusky was fired and duly charged.
Paterno's position was head football coach, not head detective. He took the story his assistant coach told him to those who were responsible and were indicted after a three year investigation.