Well you raise a number of issues, but the topic of the thread is Sandusky's guilt (or not), so I'll mostly stick to that.
First off, I'm far from an authority on the particulars of every accusation against the man, but I followed the media reporting pretty closely, statements of jurors, language of the related indictments, that kind of thing...and there is not a shred of doubt in my mind that he engaged in a pattern of criminal sexual behavior toward minors over the course of a number of years. There was certainly no doubt in the minds of the jurors. At trial, Sandusky himself did not even deny this.
In one incident in 1998, Sandusky, when confronted by a victim's mother with detectives listening in a nearby room, admitted showering with the woman's son, said he couldn't be sure whether he had touched the boy's genitals, agonized that he could not be forgiven for his behavior, and wished he were dead.
As for the infamous 2001 shower incident witnessed by Mike McQueary, based on the documentary evidence of what Mike saw, what he reported, and what he testified...and against the backdrop of multiple other reported incidents and charges...I think a person would have to suspend their powers of reason to conclude anything other than that a minor was sexually assaulted in the shower that night by Sandusky.
Is it possible that there are discrepancies or holes in the stories of one or more victims? Maybe. But when you look at the preponderance of the evidence and connect all the dots, the screamingly obvious conclusion to me is that Sandusky was a serial abuser. Alternatively, a person could deny or rationalize the evidence in favor of the theory that Sandusky is the innocent victim of a vast conspiracy. Personally, I can't think of a reason to go down that rabbit hole.
Looking at the case from the viewpoint of a devout Catholic, I see some depressing similarities in the psychology of some decent and intelligent people who, when confronted with a reality too painful to process because it challenged comfortable beliefs about their religion...even about their own identity as human beings...fell back on denial and far-fetched alternative theories. This is a familiar and very human emotional response. I didn't buy into it with regard to the Church and I'm not buying into it with regard to Jerry Sandusky.