From watching too much 'Live PD' I'd say she made an illegal lane change, had expired registration or was driving a bit too fast.
Traffic cop pulls her over and gets suspicious and asks her if he can have a dog come out and look at the car.
Knowing she's not carrying any drugs, she consents and says "Si." and then the dog 'alerts' on the money.
She was not stopped by a traffic cop. She was stopped by the Fort Bend County Narcotics Task Force’s interdiction team. They always use the ruse about a traffic violation. Not long ago and 18 wheeler carrying a large CAT excavator in Fort Bend county was also pulled over for traffic violations and upon inspection, they cut open the boom with a torch to find over a hundred pounds of cocaine. Knew first hand of two drivers making a run into NYC with a pot shipment in crates on a flatbed, contact didn’t show so they went back to NJ. They were also pulled over for a traffic violation . Again the dogs were brought out. Only through court records did we find out they were being tailed the whole trip.
They bring the dog whether you consent or not, and he will alert whether there's something there or not.