In Dragons of the Summer Flame, Palin Majere was captured after a quick battle by the Knights of Takhisis. He was released to Steel Brightblade in an effort to get a ransom out of him: the portal to the Abyss was to be opened. Now, while he himself did not open the portal, it was opened. He even told the Knights this, and the Knight-Lord exclaimed as such.
So, his ransom fulfilled, were the Knights not honor-bound to release him?