Does this even exist? Is it on a 3 month spawn timer? Seriously, I’m offline for work every other month and it’s the only chest I need for puzzle performer.
I haven’t seen it once, and at this rate I’m going to have periodic destruction done and Aqua Team Murder Force before I see this accursed chest become available for the meta achievement to get my damned crab.
For me it was Easy Green. Got it like two days before I finished the meta-achievement. The game doesn’t hate you; it’s just unlikely that on any given day, Easy Red in particular will appear. It sucks, but try to check Nazjatar world quests every day if you can, and it will eventually show up. Save your anger for when you have Periodic Destruction and Aqua Team Murder Force done and it still hasn’t shown up. 
I still need a couple of these.
It looks like I might finally get them around the same time I finish the meta-achievement. I haven’t been very diligent about this stuff, either for the companion dailies or the puzzle chests.
But even if you are perfectly vigilant every day it still must take a while.
Couldn’t you simply open the Wow companion app and check what world quests are up, so you don’t have to actually log in.
Easy green was the one that took me the longest. I think it took 3-4 weeks to pop when I started watching for it.