Is Sauron Frodo's shadow?

[Mithadan]

I am doing something that I usually do not care to do. I am replying to a post without reviewing the thread for context.

Here ends the Silmarillion; and if it has passed from the high and the beautiful to darkness and ruin, that was of old the fate of Arda Marred; and If any change shall come and the Marring be amended, Manwë and Varda may know; but they have not revealed it, and it is not declared in the dooms of Mandos.

Feel free to disagree, but I very firmly believe that this is Christopher speaking, not JRRT. This is an apology if he got it wrong from what his father intended, which, in retrospect, was a valid apology.