You knew when it was a tough fight. The weak waste away. Let him do his job. Keep the faith, shut your mouth and enjoy the rewards. He is in the trenches,,,not you,,, there are things that you do not see.
As a former Big 4 Auditor, all I'll say is that there's far more that goes on during the review of the financial statements than simply creating the reports. Accounting is an incredibly intricate topic, and if they discovered the error, they likely have to rebuild almost everything from scratch, while running tests to ensure that no other errors are likely.