There indeed do seem to be some rare instances where girls are kidnapped off the streets and forced into slavery. Still, the notion of kidnappers seeking out random victims in Redding seems unlikely, not just for the location, but also the idea that an attractive white woman being kidnapped from the affluent area of Redding wouldn't be national news.
But what also bugs me about this "kidnapped into sex trafficking" theory is this:
Kidnappers cover their faces only to keep their victim from identifying them upon release. If they're planning to sell someone into slavery, or kill them, there is no reason for them to conceal their identity.
Of course, you can't reason with crazy, which whatever happened is surely full of. So, anything is possible. But, again, Occam's Razor.