Now, as for the episode "The Star of Sultan Saladin", I have the following to say.
I have narrowed down the possibilities for hiding places for the hidden half-pendant to 1 of 2 locations, but each one is contingent on where the last Temple guard was:
1. If the 3rd guard was in the Heart Room, then the half-pendant would have most likely been in the Spider's Lair somewhere.
2. If the 3rd guard was in the Room of 3 Torches, then I'm thinking that the half-pendant was hung on the Ladder from the Dungeon to The Room of 3 Torches. (too bad we never got a glimpse of that ladder)