Ironwolf, D3 is already dead. >>; Also, you can't get Sneak Attack off against it because you don't have Combat Advantage against is from that position.  It's part of why I suggested that you wait for Isengrad to take his turn first.  If he shifts from H12 to G13 on his turn, then you can move in to H12 yourself and gain Combat Advantage by flanking with Riya.