I was having trouble with the internet yesterday and a storm kept knocking it off which kept logging me off but I have been playing in the palace when I noticed something odd. Sometimes at the end of the battles with Pariss and Hyksoss the boss chests don't appear. This has happened a couple of times now just letting you know.
It happens to me too. Not only him but any boss you're fighting, if you have someone standing on where the boss died, it won't appear. I hope they would fix this.