Is anyone aware of CoD: Black Ops 3 being broken?

I don't know if this has been posted here before or even where the best place to get this noticed but something needs to be done. I know this is an older game but please hear me out.

In the zombies game mode there is a map called Gorod Krovi which was released in DLC pack 3. Now in these zombies maps there is a quest, or Easter egg, to do certain things in the map in order to unlock the ending which unlocks the achievement for that map.
The problem happened after the release of the 5th paid DLC called Zombies Chronicles. Something got broken and now every time you finish the last step in the quest/Easter egg the entire game crashes and you can't get that achievement. This is 100% reproducible.
This achievement is actually necessary to further unlock things in the next map Revelations the 4th paid DLC map pack.

It is literally impossible to unlock several features unless you have that specific achievement because of how the game tracks your progress and further breaks several key features advertised in DLC 4. People are paying/have payed for this content and cannot
use it. Many people have complained about this on reddit and Call Of Duty's own forums as seen

HERE.

Treyarch, the game company who made Black Ops 3, posted an update saying they had a fix in the works and it would come soon. That was over a year ago with no sign that a fix is coming. I personally was lucky enough to complete the Easter egg before the problem
came into play but I also like to help out other in doing the Easter eggs who haven't done them before, or even just to replay them for my sake and I cannot do that anymore. Many have attempted to contact Activision / Treyarch and while both companies have
acknowledged the problem there has been no mention of a fix since late 2017.

I'm very surprised Xbox allows broken games and paid DLC's to be sold when there is clear evidence that I'm buying a broken product. Can anyone here confirm that this is a problem?

:)