When Chloe goes to question Dave the gaffer, she identifies herself as an undercover cop. The whole point of an undercover operation is to obtain information without raising the suspicion of those being investigated, and the blowing of one's cover should be avoided at all costs; it's rarely, if ever, done deliberately.
The murder victims are two women and a man, but at one point, Maxie asks a suspect "What can you tell me about the three girls who were killed?"