Kill 20 Lv 7+ near Tortuga Graveyard

[Amelia Heartburn]

I'm having the same sort of issue...I think.

Quest says someting like, Kill lv 7+ Skeles to recover 6 dice in the Jungle.
My tracking beam does not work nor does it show "quest updated, no dice found"
I have gone to Tortuga Graveyard and have a difficult time finding lv 7+ Skeles.
Am I in the right place and what am I doing wrong???
Any help would be greatly appreciated as three days of this is getting quite fustrating!!