One was bringing the money the other did not have. That does not mean she consented to sex with two men.
Well, she sort of did consent, pending payment. IMHO, the judge should've gone with rape charges against all four, then added the theft of services charges against the two who said they'd pay. That way, if a jury bought the consent argument, those two guys would still be on the hook for the lesser charge.
Perhaps one of our FR legal eagles can explain whether *illegal* services can, in fact, be stolen.