I will give every person who posts in this thread one hundred pounds if we the audience hear the Doctor's name being spoken out loud in this episode. (As opposed to him whispering it to River Song.)
If we hear a name, it won't be real.
I imagine Clara would say, "You said your name was..." River will say, "No, that's not his name." And the Doctor will say that he needed to say something and, because of some escape hatch to Dorium's prophecy that we didn't know, so he made up something on the spot.
It's a Moffat finale. That's the way these things go.