With the Second Necromancer dead for good, the reclamation for the Kingdom of the Deep Sea was complete. All of the merfolk who got killed and turned zombies via necrosis has been turned to dust and has already dissipated in the water. Due to the disease, it wiped out all of the population of the Kingdom of the Deep Sea, leaving the whole kingdom as a "dead" place. Without anyone else living there, it was good as abandoned already and I doubt any merfolk would live here again especially with the event that wiped out the entire merfolk in the kingdom, it's a bit doubt if they will still hope to live here unless they are too attached to the place and isn't afraid of the previous event.
In the palace...