Quest "Just Checkin' (ID 13099) in Zul'Drak has been marked as obsolete, and in fact it can't be obtained form questgiver. Wowhead states the same in its quest entry: https://www.wowhead.com/quest=13099/just-checkin

This quest has been marked as removed in ATT for years, where do you see it?

This quest is marked as removed in ATT as expected.