Another "me too" here. I just reached 100% bestiary progress for Revenants, so I went to the bestiary to look them up. Couldn't find them anywhere. However, clicking on the line in the log that reported the progress, I do get a bestiary page to come up.
The picture shown is of a skeleton, but the text mentions: "Revenants are undead that have devolved beyond even the relative intelligence of a gul." And they are drawn in the game with some amount of flesh on them... So I'm guessing that maybe Revenants have been cross-listed into two different categories, part Skeleton, part Gul, and that gets the Bestiary confused?