Nostalrius Begins - Quality wow vanilla realm (1.12)

Hi my rogue poison quest was canceld(I forgot to use the item before I talked to the dwarf). He killed me and the quest was canceld. I'm not able to restart the quest or continue it. Any tips? Thanks!

There's no need to use the flare. If you use the /salute emote on the dwarf he will become friendly and you will be able to turn in the quest "Deep Cover" and pick up the next quest "Mission: Possible But Not Probable". If you have abandoned the quest "Deep Cover" you should be able to pick it up at the rogue trainer "Shentul" in Orgrimmar.