Arawil combined a sickly-sweet temperament with headache-inducing disrespect for the ship's commander and crew. This included referring to Gul Macet by his first name of "Akellen" without permission in front of the entire bridge crew--a grave social transgression in Cardassian culture.
Despite what should have been obvious evidence of Macet's thorough contempt for her, Arawil never suspected his treachery, right up to the moment when the Trager's senior staff quite literally caught her with her pants down after deliberately engineering an electrical hazard in her quarters' private head. From there she was beamed into cryostorage to avoid triggering any signals from her termination implant that might notify the Dominion of her death, and replaced a surgically-altered Cardassian, Mindesa Rhos.
Rhos would use her position to eliminate Arawil's Jem'Hadar contingent and continue to impersonate the Vorta in official communications with the Dominion after the Trager regained its freedom. (Star Trek: Sigils and Unions: "The Thirteenth Order")