Oh, you can find a regular pearl on Route 115's beach!
Oh, then seems that I bruteforced my way into the scene... Thank you for clarifying it!
Edit: I finally found the pearl! It seems that even while using Aura Lapis, the item was hidden entirely, although I do not know if it is only on my end :(
I've just checked it out. It indeed seems to remain invisible which was odd. Managed to fix it, however!
