Yes i did talk to jonelath but he still has a question mark over his head meaning the quest is still unfinished.
Actually its happening exactly as u said.Not only the ultimate creature but also moor and alrik which i should slay for the 'a hunting we shall go again' quest also disappeared..i only saw them in a brief cut-scene,but they did not appear afterwards in-game.Unfortunately i applied the patch just yesterday after the saves and as u said,it has not been rectified and these 2 quests(a hunting we shall go again,out on a limb) remain in my quest log.But i shall email larian support and ask them for help.Thanks for the advice.