In the very first scene when Maddie is looking at the art pieces, there is a radical change in her voice when she says a sentence turning to the woman who asks how she can tell they are fakes. She explains "The signature..." in her first recorded voice, but then continues the sentence "is in Arabic, not hieroglyphs" in a deeper, louder voice clearly overdubbed and poorly edited.
Before Maddie arrives, Andrew & Elodia discuss how great the new artwork looks on the wall, the following morning Maddie interrupts Andrew working out where to hang the same.
All through the film, the license plates of the jeep change from the fictional island to Florida. The movie was filmed in St. Augustine, Florida. Landmarks are clearly visible all through the movie.
When Fitz arrives to lead the group for a day-trip, the first shot is of the jeep coming through the gate, in the reverse shot a drone can be seen to the left of the jeep, just beside the tree line.
Tilky Jones has a rather large tattoo on his left arm. Apparently, that didn't fit well with the character, so during the snorkeling scene, when Fitz climbs back into the boat, apparently there is a wet sheen to his arm, that causes the digital editing effect to fail, revealing parts of his tattoo. Actually, there are several areas in the film where parts of the screen seem to shimmer a bit as if a green screen is not working well due to lighting conditions.