I'm playing on PS4, so console commands are out of the question.
This happens all the time in Skyrim. Do you have a save from before you did get the quest?
The normal advice here is, to wait 30 in-game-days. After that, the dungeon should be re-filled. But I'm not sure if this helps you with Halldirs Cairn, especially since you wrote that you did already kill another drauge.
Work?
Do you only play to fill a youtoube-channel?
As a re-starter, I simply enjoy every moment of playing Skyrim. Even if I'm telling myself that the character I was playing yesterdays evening for 2 to 3 hours is just boring and I should start an other one, I don't feel any regret.
It's not that, I just hate replaying content. I do enjoy Skyrim but erasing 3 hours work of effort just to get by a bug is irritating no matter how much I'm enjoying a game.
Oh, and here's the kicker, when I did the intro quest to the Companions a second time, Farkas didn't even send me to Haldir's Cairn!