The only mention I've seen of the area being known for
possible trafficking is the previously linked Daily Mail Article. It's the Daily Mail, IMO they put much of south Texas as a "gateway to trafficking" to attrack readers with a more lurid headline. The area in which she disappeared from appears to be a very large upper middle class subdivision - nice area, one I certainly wouldn't be concerned that my daughter would be taking a walk in. No nearby large roads, lots of family homes.
Street View · Google Maps
This is just a sample listing (not the home she was missing from)
on her block. Homes sell there in the upper 200's to low 300's. which for San Antonio is average.
https://www.redfin.com/TX/San-Antonio/11051-Caspian-Spg-78254/home/48645397