The level 2 BF key is in the area patrolled by the DKs. <span class='standouttext'>Spoiler : </span><span class='spoiler'>From the entrance, head west, north and then east (follow the right hand wall) to a side storage room.</span> (highlight the text to read)
As for fighting the DK Patrols, I had hero my archer set to aggressive, to start attacking as soon as the patrol showed up, and kept my DK warrior up front.
