I really dont know if this works or not but I seen it have been trying it but I think Im in the wrong spot hard to tell maybe someone here can figure it out and let me know!!
This one is thank the guys of EGM. You probably know this, but this
cheat lets you go underwater with Yoshi and easily beat Shine 8 (one of
the hardest shines.) Anyway, go to the person with the durians. (Go to
the right slightly from the start. Turn underneath the bridge. Go to
the left and you'll someone the left with a box.) Go to the left of her
and try to run through the wall. Get through it and you'll be
underwater! Do this with Yoshi to easily make it to the island in Shine
8.