That does not explain why she should not be able to look at the financial reports. You should be careful to not ascribe pure motives to the Bishop. Not saying he isn't honorable, but even otherwise honorable people do things out of character for reasons they'd rather not share.
In the end, it is my guess that she has good reasons to be suspicious.
No doubt the voices in her head are telling her she does.
I'd be very surprised if she did not have access, like all other parishoners at every Catholic Church I've ever heard of, to annual reports of income and expenses.
It sounds to me like she wants the right to audit the Church and nitpick over ever invoice and expense. Maybe criticise the pastor for buying brand name laundry detergent for the linens instead of using store brands. Who knows?
If she suspects malfeasance of some sort, she should report it to the diocese or the police. If she's just nosy, she should get an ego check and realize it is not her role.
SD
For goodness sakes, read the article. It says she wants a line by line report, that's something quite different than a regular financial report that most churches give to their parishioners. As someone else pointed out, she wants to know how much is spent on paper towels.