#3 - March 6, 2018, 12:08 p.m.
Hey there Evefh,
What usually happens with a seemingly 'stuck' or missing Class Hall quest, is that a quest was not picked up or abandoned. Most of these quests start in the Class Hall but they can take you all over the Broken Isles and sometimes even to pre-Legion zones. You would then have to find the location and NPC again where you left off.
In this case your Rogue was sent out to find Fleet Admiral Tethys in Stormheim but you never continued that NPC's quest chain. Have a look back with him to pick it up again.
Websites such as
Wowhead can help you to find exact locations if needed. :)
Good luck!