Gundabad orcs spawn everywhere around the Misty Mountains, but not every Orc from the north is from Gundabad. Those Orcs conquered Moria, they had a ruler living in Goblin-town, they ravaged and pillaged the lands around the mountains and calling their faction just "Gundabad" is just not correct, in my opinion. It's as if the Gondor faction was named "Minas Tirith"! But I'll understand if "Gundabad" was chosen because it is a short word that fits well in the mod's GUI or, let's say, it conveys in a summarized way where those Orcs are from.
My suggestion is to change the name of the Gundabad faction to one of these in the poll: