These networks often bring girls under false promises. They offer to cover their visas or travel expenses, lodging or whatever, but once they get to the country they learn they are in debt, and not only have to pay for everything, but also the traffickers get most of what they make. Also, their passports are taken away, they have to sign questionable contracts, have sex with a certain number of "clients" a day, their families are threatened, you name it!
I once attended a class with a human trafficking and smuggling expert, and he presented multiple cases, not only about foreign women brought here, but also about Dominicans abroad. Sometimes they make them sign illegal contracts.
Even though there are cases where the woman, who is allegedly coming as a dancer or an escort, knows that her activities might include "more than dancing", that doesn't mean they know they'd end up beaten, literally sold, isolated from their family, having no documents, forced to have unprotected sex with whatever amount of men someone tells them too, etc.