I believe there's truth in some of that and in some Kosta is expressing his personal take on history. And a point, you seem to miss is he's illustrating that claiming to "possess" the only God does not make it so.
In addition he is exercising his ability to read and discuss the canon in his lights. Now THAT part you should at least appreciate.
Facts show that the Scriputres have been tampered with, intentionally or accidentally, it doesn't matter. The main message in the scripture is preserved, despite all the little additions and deletions and transcribing errors and, let's not forget, those books that have been identified as lost.