Shadowlands related NPC disappears?

I was in mechagon, and I noticed a NPC with a quest, started with an X. I started to read the quest text, it mentioned Shadowlands then someone else walked up, and the NPC disappeared.

What is going on here? Surely blizzard didn’t design something that punishes people who actually read the text?

I guess they can be spawned via the mount. Weird that I have to use google to play WoW. That orb was not very discoverable