BF quest items and monsters are placed randomly on the third levels of the dungeons, so it is possible for any particular dungeon to have none, one or multiple items or boss monsters. A couple people have run into a bug where some or all of the quest items or monsters were missing, and could not complete those BF quests for that act.
Have you installed the
patch, or do you have an already updated version of the game (1.47 or 1.49, as shown in the bottom right corner of the main menu)? IIRC there was a bug in the original release with one of the act's BF quests, and I think it was act 2. If you have a version number less than 1.47, install the patch before moving on to act 3, for best effect.
The only difference between 1.47 and 1.49 was the removal of the copy protection, to provide support for the game in Vista.