Yes that’s the case for Evokers too, so there are people who cleared heroic Sark every week but still don’t have it. Knowing that your key cap is lower than someone else of the same or even less skill because of RNG has been a big gripe.
Again, doesn’t impact me as my 15 keys don’t require the legendary but I can see it becoming ugly by the end of the season if it’s keeping people from the top .01% title