Need Help With Beneath The Depths

During the Beneath the Depths quest, you need to get the faded map at the start. When you go in the skull, the pirate will tell you to take a block of emeralds, go to the front of the skull and throw "in the middle of that raised thing." I've looked around the front for 30 minutes and I can't find anything. Please help!!

 

The room that you're in when the pirate tells you to throw the emerald has a tombstone in the middle and you have to throw the emerald into the carpet at the base of the tombstone

 

Thanks!! They need to change it because it says at the front of this tomb.

 

well the grave that the hopper is in front of is a tomb