You have to do a quest in Idyllshire to be introduced to the branch in Rhalgr's Reach.

If you haven't unlocked the Scrip exchange in Idyllshire, you'll have to get a quest to go there from Mor Dhona. Then do another few quests in Idyllshire and then they'll refer you to Rhalgr's Reach.

After which you'll be able to interact with the people in Rhalgr's Reach.