If you skipped the dialogue with the old hag, you to swim to the island and get the meat. Simple enough.
It Came From The Swamp!
Beware the swamp monster barry
When you see the circle splashes stop moving Barry will get you. Just watch the thing swim away from you and swim backwards to the island.
Just move when he isn’t near you get in, get out, get BACK in, and you guessed it… deliver the meat.