During the Scarab demonstration, the same man (wearing a checked jacket and baseball cap) jumps off the burning ship twice. It's even the same shot shown from a different angle.
When Mitch and Buzz are out on the boat, the direction the wind blows Buzz's hair keeps changing.
When Buzz falls into the water, a small boat is visible in the background behind him, meaning he and Mitch are not as isolated as we are led to believe.
When Stephanie shows the newspaper article to Summer with the headline "Socialite Suspected in Hotel Death" you can see repeated paragraphs of text.
The only lifeguards who qualified for the trip were Mitch, C.J., Matt, Summer, and Stephanie. But during the scarab demonstration, Barnett is inexplicably present, and C.J. is not.
One of the old newspaper headlines read "Victims Death Ruled a Suicide." It should be "Victim's", with an apostrophe.