But doing it how you're suggesting how DPC 'might be' telling it, doesn't have anything to do with being predictable. I think it would have more to do with being a horrible writer. DPC isn't the best writer out there, but he's not a horrible writer either. He's more of an semi-experienced enthusiastic writer. I strongly doubt even he would make such a literary 'faux pas'.
Now, I'll grant you this caveat though, it is clear that the MC still hasn't read the diary completely yet. So the answer may still lie within it's pages for Ep 10 or 11.