Looking at the list, we got almost every half-pendant location for season two and three. Only three episodes remain:
We all know that the last guard was in the Shrine in "The Walking Stick of Harriet Tubman". So that means that the half-pendant was most likely on a bottom floor room. In the past, we have theorized that it was in the Swamp - which makes perfect sense. However, we don't get a good shot of the Swamp in this temple run. But it would make sense if it was in the Swamp.
Then we have "The Snow Cone of Mount Kilimanjaro" where the team was too stupid to make it far through the temples. One thing to consider here is that the King's Storeroom opened up from the Pit. It is possible that the half-pendant is there. However, I don't think so considering that I am pretty sure the last temple guard was in the Quicksand Bog. So I am sure that it was on the bottom floor of the temple and the team was too stupid to find it.
And finally we have "The Bent Shaving Pan of Jedidiah Smith". Not sure about this one, but Irish did meet a temple guard in the Tomb of the Headless Kings and Ancient Warrior. The last guard had to be in the Ledges, because if the team encountered him here, then the one room away guard would be irrelevant. But it could be in a lot of places like in the Jester's Court similar to "Xerxes".