During our last run through Bilerot Burrow i created a map from this place as well. The whole dungeon is very straight forward, but maybe a map can help with the initial orientation. Bilerot Burrow is located inside the Inevitable City (near Monolith) and is the harder one of the two capitol dungeons. If your group doesn't have enough wards you'll be better off going to Bloodwrought Enclave. Some of the trash mobs are harder then the bosses, but you'll find out very quickly if your group should be inside Bilerot or not, it's a gear check right at the beginning.
There are three bosses inside the dungeon:
Ssrydian Morbidae (Sentinel shoulders & belt)
Bartholomeus the Sickly (Sentinel gloves & belt)
The Bile Lord (Sentinel chest & belt)
Bilerot Burrow MAP v1.1
Update 04/12: added the location/name of the missing hero.