If you believe, that the quest is bugged for you, please contact Amazon's support. I can't help you with ingame bugs unfortunately.

Описания берутся напрямую из клиента игры. Завтра обновлю до текущей версии, посмотрим, изменилось что-то или нет.

The list shows all possible sellable items for this merchant. Not all of them are on sale at once.

Can you name one such quest so I could look for it?

Thanks for the report. Indeed the starting NPC for this quest is located in Kalaja.
However, the game designates this quest as one belonging to Nameless Valley zone. That's what the data in the client files says.

Thanks for the info, but that's not a bug.
The game calculates most of the parameters for the monsters at the moment of spawn. That's why they're are not present in the client's data.

Thanks for the report! Fixed the doubles.

I'm getting everything from the game files.

Thanks for the report! Fixed.

Double check if you finished the prerequisite quest for this one. Also, you should have quest https://lostarkcodex.com/us/quest/6003043/ finished or not started yet.