If you would rather go on your assumptions about how the quests are "linked", rather than fly to Hinterlands and attempt to pickup the quest yourself, thats fine. I have several people who have verified this and the other quests are attainable in-game. In fact, the author of the second bugtracker page you linked:
https://report.nostalrius.org/plugins/tracker/?aid=810 specifically states that he was able to complete the first quest. He may not have given level and rep info but according to him he did complete it, meaning he must have been able to accept it in the first place. Either he is lying along with everyone else or I really am correct and am in fact experiencing an issue specific to my character.