His name is indeed Bornhold
Their goal is to mostly about converting other nations to the Light as they see it. They use armies, persuasion, and other methods to convert countries.
They mostly kill anyone they think is against the Light. Think of darkfriends like the red scare or the salem witch hunts as they will accuse basically anyone of being a dark friend. Also the Commanders plan is to unite the nations against the Dragon Reborn as he thinks he is a false Dragon.