Castle Nathria Legendary's [In-game]

[Marsilea]

Title: Castle Nathria Legendary's

Type: In-game

Description: 

Since the raid content is being released every 2 weeks certain classes like warlock have to wait 5 to 7 weeks for their BIS legendary's since they drop from stone legion generals (https://www.wowhead.com/item=183367/memory-of-demonic-synergy)  or Denathrius. (https://www.wowhead.com/item=183362/memory-of-a-malefic-wrath) 
Is it possible to make the legendary's that drop from the end bosses in castle nathria to drop from something like dungeons aswell, or buyable from a vendor?
Since its understandable that you all want to release content in a longer period of time to make sure everything is working correctly, but having to wait 5 to 7 weeks to be able to get your legendary seems a bit overkill.