Corrosion Prevention

The quest “corrosion Prevention” in dustwallow marsh does not appear to be working. Using the quest item on the oozes just kills them instead of ‘melting’ them and updating the quest. Since the quest uses and item to do the work, I’m not attacking the oozes (I’m lvl 120) so that should have nothing to do with the quest working properly. I use Recount, and it does not detect damage at all. Even removing all gear does not seem to help (which it usually does with quests that require you to damage the mob before using a device).