The breadcrumb quest Blackwatch (https://www.wowhead.com/wotlk/quest=13106/blackwatch) is shown as available on the map, but cannot be picked up as follow-up quests have already been completed.

Run this command, do you get true or false?
/run print(C_QuestLog.IsQuestFlaggedCompleted(12897))

I also noticed something erroneous with those quests, Where Are They Coming From? and some other
Those quest chains need to be polished, and i didnt get to that zone yet :(

I got true.

Should be fixed