What happened to Holly when she and several others went to Holly's rental home to help Drew pack in the novel, The Whole Enchilada?

After Holly’s death, Goldy and several others accompany Drew Ingleby back to the rented house by the lake where he and Holly lived. While the others help Drew pack, Goldy steps out onto the back deck and walks to the end when she sees an envelope marked: “DREW! HERE’S YOUR MONEY! sitting in a planter. The deck immediately collapses sending Goldy into the lake below, where she would have drowned if Julian hadn’t saved her.