I am the friend of frustrated.
You are correct thats the mission we need to complete Tigranes, we didnt go and talk to odo, at the legion chapter house, we went to Stone Bridge instead to continue on with other missions and defeated the Old Gent but before we continue we have to make sure all other Quests are complete and this one is blocking our path because as far as I can tell we waited to long to talk to ODO and it has decided we missed our chance. Interesting that when we came back from Glitterdelve mines ODO had in fact already travelled to the "Grand Chapterhouse" via Causeway earlier on and was not at the original "Legion Chapterhouse" which is where the quest says to talk with him.
I am really keen to continue the game, but I not sure if that will be an option if we cant bypass this.