I've been to the sealed chamber but I cant get into the island cave in Pokemon emerald?

You may have been in; but may not have been through the Braille challenges. When you dive, the first Braille says; Dive here, so you dive and you come up in the sealed chamber. The first Braille inside the chamber says: Dig here, so you dig and the door opens; revealing the next part of the chamber The second, and final Braille says: First comes WAILORD and last comes RELICANTH. This first guy got it mixed up. Three doors open. If you meant you cant get inside the door to Regice, according to my memory, you run around the walls of the cave with no collisions.