|The Chamber of the Crossroads|
'You will always have my respect for what you did before the Doors of Durin, avenging my poor son with your excellent weapon, but I must be honest with you: I believe you are wasting your time. As long as you will be traipsing around in the dark looking for this flight-of-fancy forge, you might as well accomplish something worthwhile, Name.
'There seems to be a large goblin presence among the Silvertine Lodes, far to the south and below the Great Delving. As long as you are searching for this fabled Heart of Fire, you may as well slay goblins while you do it -- especially the ones that have moved into Gamil Filik, the Elder-mine. The goblins are many, and bringing an ally or two might be a good idea.
'In fact, why not steal some of their maps? They have long lived here in the darkness, and their crude maps may show the way to this mythical forge of yours, as well as being useful to those of us seeking paths that actually exist.'
Brogur is skeptical that the Heart of Fire even exists, and wants you to at least do something about the goblin problem while you search for it.
Bring crude maps to Brogur
Brogur is in the Chamber of Command, up the eastern stairs in the Chamber of the Crossroads, located at the southern entrance to Durin's Way, north of the Great Delving.
You have slain many goblins and collected their maps while searching for the Heart of Fire.
Bring crude maps to Bosi
Despite what you were told, only 2 of the maps are in Gamil Filik. Go down the main tunnel from Deep Descent, turn left, enter the camp, turn left and left down the tunnel to a tent at the back. Map is on a crate by the tent.
Second map is due east along the north wall to the northeast corner of Gamil Filik.
Now go back to the main tunnel and through the hole in the wall. Descend until you reach the tracks. Go left and down and when you get to wood platforms the map will be just across from you.
Go back to the 4-way track intersection. Look south and up. See the last map? Walk south to second 4-way, then west, then south. Watch the east wall and you will see an opening. Walk through there and you will reach the platform. Turn left and up the ramp to the last map.
Remember, Sneaks, Guards and Scouts abound.