Esther volunteers to cross the border to get help for Irene, saying she'll do it even though it means she will be disqualified. But Carolina could've crossed the line without anyone being disqualified, since she already admitted she worked for the show and wasn't a contestant.
Daniel discovers that the button to summon a helicopter isn't connected to anything. None of the characters ever question what happened to Veronica, who supposedly pushed the button to leave. Veronica may have left by helicopter (or she may have never left), but she didn't summon it by hitting the button.