Who says a Treasure Island has to be on the sea? There are Treasure Islands under the sea as well.
Back then, the Red Fire Old Demon discovered this place because two Great Demons were fighting, shattering an entire Spirit Island. After killing the two Demon Beasts, the old demon pondered the remnants left on the scene.
Immediately, he sank this small island; in the Demon Beast Abyss, the disappearance of an unremarkable small island wouldn't draw anyone's attention.
Moreover, there were traces of Demon Beasts fighting on the scene.
Only then did the Red Fire Old Demon lay out his Treasure Site here.
"Obviously proficient in fire Cultivation Techniques, yet the Treasure Site is underwater."
These Nascent Soul Cultivators are more cunning one by one, but before Lin Chang'an came here, he had already circled around the nearby area several times.
