As to the unverified map in the desert. I have been to that area many times now and no chest has popped. It's a fight with 4-6 gnoll casters and a nasty whirlwind which easily knocks someone over into the boneyard. It's quite a fight, more difficult than most of the other chests but nothing has popped there. I'll keep looking when I run the desert but as of right now Id say the chest does not exist.