... the following quests They're one of those "run this zone a million times" type things from a few expansions ago. I don't plan on figuring them out and running old heroics repeatedly to get rid of them
It's how the quest system is coded. These two quests are auto-granted (you can't accept or decline them) when you start another mission which in turn updates the non-deleting quests. In any case, you'll be able to have them removed another way.