Turns out Hamun was looking for a gem to control Agatha the Banshee so he could ask her the location of a powerful Necromancer Book. The party already knew the answer to this and so told him. In return Hamun gave them shelter and learned he was no where near the Wave Echo Cave (and neither were the party).
His zombies on standby guardian the entrance to the fort where the Old Owl Well is located, the party rested and awoke the next morning to the disturbing sounds of orc drums. An attack on the ramparts and the drawbridge was underway. Shara the Cleric noticed them first and so Hamun flew into action and choked the entrance with 5 of his undead servants.
The battle was engaged and within two minutes the orcs were hacking and pushing their way across the drawbridge, decimating the zombies that were there to be roadblocks. The party was not idle however and via missile shots and brave melee attacks the orcs were beaten back. Hamun was left weak and exhausted from controlling the undead but healed by Shara.
The party, with the new found knowledge of a new friend, rested until the next morning and set out for the general area of Wyvern Tor to search for the Orc lair!