When you say : for kills, handling through quests, do you actually mean patching/creating many NPCs Perl quest files ? There can be an orc_centurion in several zones, some of them actually "dinging" the quest..
As the kill activity is very common, having a lookup table (ID of activity, ID of mob) seems worth doing. Especially as you can attach this list/set to the activity in a field once it is loaded from the DB. It probably is not in the scope of Live-like, but extending this to several activity types you could then have activities that accept looting "any rusty weapon". Not trying to make my shopping list for the first implementation, just trying to keep doors open here
Or may be you thought of another way through quests ?
As a professional programmer let me say one thing : filtering on the name (or a part of the name) will inevitably create unsolvable situations, or to say it bluntly, it will suck. It always does when you start doing such things.