The word wall is in there as I have just got through it and collected the Slow Time first word.
If I remember correctly, it is easily missible and if the music did not kick in I would have missed it as well
In the Labyrinthine, Tribune section, it is in a room with the throne, before the corridor with pillars on each side.
There are a few time you will meet spectral warhounds, so I think you are just not far enough, as the only Ghost you see after this word wall is Savos on his own, as the others have dissappeared.
Hope that helps
Finally found it! But it's interesting -- the variations in different peoples' games.
It was in the Labyrinthine, Tribune section, it was in a room with a throne, the next chamber had pillars on each side, and I did hear the music. But in my game, the Draugr Deathlord had a Spectral Warhound, and the room after that had
three ghosts, Savros and two others, talking about one they'd lost. Odd. But after you'd convinced me I was in the right room, I kept looking and found the Wall with the Word. My problem was because of the Spectral Blue Warhound -- I kept seeing what I thought was
that dead body across the room, when it was actually the Spectral Blue of the Word!

Thank you, all.