I am not seeing LoB being pugged on Cannith. The Master Artificer is being pugged fairly regularly, but not LoB. The few I see are mostly heavily filtered guild runs looking to fill a few particular spots or ones that take to long to fill and give up. I have about 12 MA's and 0 LoB. It seems the initial reports on the raid being difficult has made many people skip it. Maybe make normal a bit easier and increase drop rates in harder difficulties. Add +3 tome chance to hard and +4 to elite and epics.
Perception is often greater than reality in DDO. You probably wouldnt have to change it much - just say you made it easier in the u12 release notes and I think people will start giving it a try.