When they are looking at Tony's cell phone texts with a mystery person at the JOC, Tony's texts are on the left and the mystery person's are on the right. Usually, texts on cell phones are the other way around. Tony's should have been on the right.
An agent with experience working undercover would never attempt a sting operation without first coming up with a plausible backstory, they wouldn't just make it up as they go the way Sula does.