Scout Master Kilkarn asks you to speak to his scouts and help them with their tasks. Only one scout at a time can follow you, and a scout's step of the quest will only update if that scout is following you, but the scouts will assist you in combat. Each scout will stay with you for 10 minutes only, so don't get distracted too much.
NOTE: The killing blow on these mobs has to be dealt by yourself or the NPC (not any of your pets or someone else). Furthermore the NPC has to participate in the fights in order to get updates. Pet classes might find it easiest to dismiss their pet before recruiting scouts.
Note: If you are a class that has a pet (necro, etc...), you will find it much easier if you dismiss it. The Scout will automatically take it's place and be like the pet.