Guide:
Northwestern Deshaan, southeast of Quarantine Serk Wayshrine.
Found inside the “Forgotten Crypts” public dungeon. At the Quarantine Serk Wayshrine follow the road south. When you reach the crossroads follow the eastern path until you are about to cross a bridge. Instead of crossing, move along the northern river bank and you will see doors carved into a cliff which lead into the dungeon. Once inside, just follow the path and it will lead you to a crossroad where this skyshard is found. Be careful, this is a public dungeon with large (4+ NPC) groups so bring some friends along.
The map pic for Skyshard #11 is incorrect. The full Deshaan map has the location correct. Please update guide.
The map is still incorrect. It points to a delve rather than the public dungeon this skyshard is actually in.