Nostalrius Begins - Quality wow vanilla realm (1.12)

The quest in STV, in which you have to kill Cozzle to get a key from his chest.
The key drops from him, but once you loot the chest in a nearby house, its empty. Tried several times, still no loot of Fuel Regulator Blueprints..

I've done this quest a few days ago, and got no problem with it

Also, in the patch note of yesterday, i read this :

--> Quest container should not be empty anymore.
--> Some quest container respawn time have been reduced.

Try relogging, i dont see any reason why it shouldnt work