This is from Sam Calagione's (DFH founder) book. It's extract, but I'm sure you can convert to AG if you'd like:
10oz British amber malt
10oz Crystal 60L
8oz Chocolate malt
2oz roasted barley
Steep all of this at 150F for 30 minutes
Add 7lb Light DME
8oz Dark Brown sugar
1/2oz Warrior Hops for 60 Minutes
1oz Vanguard Hops at Flameout
Ringwood Ale Yeast/Wyeast 1187
This is of course for a full boil of 6g. Never brewed the recipe but its from DFH themselves. One of my favorite browns too and probably my favorite DFH beer.
EDIT: Not sure why they would put a different recipe in the book than what it is (per the bottle), but its possible its just to protect their trade secret. You could brew the same recipe basically but using the hops you noted (obviously bumped up b/c they are lower AA) and carmelizing the brown sugar, if it makes you feel better.
EDIT2: Upon further inspection and thought, the boiling addition probably doesn't make a huge difference, since all you are getting from it is bittering. They could possibly use this in the clone since its cheaper for the HB and you might not notice a difference (its 15%AA compared to Liberty around 5.5%... thus 3x more hops would need to be used to bitter). The Vanguard at the end is a 5.5%AA hop similar to Hallarteau, but you could easily swap this out for an oz. of goldings...