Miracle said the teenagers, who were trying to board a flight to NY, had a small number of bags with them, but no form of identification and no adult guardians.
"They kept looking at each other in a way that seemed fearful and anxious. It just doesn't feel right to me, '" she said.
At first, the girls didn't believe they had been tricked into a trafficking situation.
The girls, who had no identification and were traveling alone with just two small bags, had two first-class tickets bought by a third person using a fraudulent credit card.
He had offered them $US2000 (£1,425) to fly to NY for the weekend where he told them they would model and feature in music videos. A sum of $2000 was promised as compensation.
The girls were reunited with their parents, who were informed by investigators that their daughters almost became victims of human trafficking.
"When I told them that they didn't have a flight home, that's when it kind of sunk in that maybe I was actually telling the truth", Sanderson said. ("They said) "No, that can't be true" - and I said, 'No, the airline says you have a one-way ticket, and in my belief, you're going back there not to do the things that you think you were going to be doing.' And they said, 'I wouldn't let anything happen that I didn't want.' And I said, 'Well, you probably wouldn't have a choice in the matter'".
A Sacramento International Airport employee's quick thinking likely saved two teenage girls from lives in captivity.
Miracle's attention to detail may have saved the girls' lives, American Airlines said.
"I'm proud of Denice and how she put her training into action to save these children", said Sacramento General Manager Aleka Turner.
When sheriff's deputies arrived, the 15- and 17-year-old girls told deputies they had met a man called "Drey" on Instagram, and he had invited them to NY for the weekend to earn $2,000 for some modeling in music videos. Deputy Todd Sanderson arrived and questioned the girls, who claimed they had just called a man they had met on Instagram named "Drey".
Sanderson asserts that Drey probably used photos of a different person and that the case would likely not be persecuted.
The teens were later reunited with their parents, and Miracle - whose name is appropriate for the rescue - is being hailed as a hero for her quick thinking.
It is not clear whether the police were able to locate Drey after the incident or what charges he might face if caught.