[NewinTexsas]

The other janitors told him to report it.

The expressed their concern to him that they might lose their jobs if he reported it. He told his supervisor. His supervisor gave him a name of someone to report it to. It was never reported.

[Tribune7]

OK, he told his supervisor and his supervisor told him where to report it. The supervisor, who appears to be the only at the scene who was not a new employee, didn't seem concerned about how Paterno would react.

The janitor who saw it was a temp. Why would he be that afraid of Paterno?

What you have here is not an example of Paterno's evil omnipotence but of people choosing not to get involved.