Did you start the treasure hunt through all exploration sites? The first drops at home base.
I have the first two steps of the portal quest done (get fort to lvl 13 and explore Crumbling Ruins), but the next step is "Explore Silent Lake". I have been exploring the lake for 24 hours now and nothing...
Check the unique events in the exploration tab. It likely moved to another location. You should find each in 2-30 minutes.
