Which files are you referring to, and how do you know they exist is they're "hidden"?
I'm not stating nor implying that such files don't exist, especially since we well know that the bishops way all too often just moved possible offenders to other parishes, which the Pope alluded to yesterday at the Vatican conference, btw.
Not this is an excuse, but we should always remember that this kind of hiding and denials is what the vast majority of organizations, religious or not, tend to do so as to protect the organization. Here in the Detroit area, we have seen this repeatedly within the auto industry. We've seen it repeatedly with political parties. We've seen it with other religious organizations besides the RCC.
With the latter, the RCC has repeatedly admitted its complicity by all too many Catholics, including many bishops, during the Holocaust. Can you name other churches that have done that? I studied the Holocaust in Poland and Israel, including having discussions with both political and religious leaders there, and as far as I know only the RCC has issued formal apologies and have clergy currently monitoring anti-Semitism in eastern Europe. I met the prior bishop in Poland and here in the States who was in charge of answering directly to the Pope on this.
Anyhow, I gotta leave for the weekend, so take care.