The "Gol Koval" quest becomes unobtainable if you've already completed "Deliverance", but it is still shown as obtainable.

https://www.wowhead.com/quest=48947/gol-koval
https://www.wowhead.com/quest=52074/deliverance

Making 48947 a breadcrumb for 52074 has been done for the next release of Grail.