Either its not clear enough of where to use the incense, or else theres a bug because ive been in every part of the deadlands, the lair, and the entrance to the deadlands, and im still unable to use the incense. Please help 
the quest text states:
Enter the Deadmines dungeon and use the Incense Burner to see into the past.
walk in through the instance entry portal, use the incense
thanks, sorry for being a noob !
if you need any help with info, head on over to the New Player forum… there’s no question too noobish 