Here's a suggestion for WooMe, if it wants to cling to some credibility or at least plausible deniability: upgrade the journo's account for free, so that he can contact the senders of those messages. If the messages are offering dates, and insisting on upgraded levels of membership - case closed. If the messages are promoting some unrelated service - the site has a raging spam problem.
And if the messages are real, I'll be a monkey's uncle.
Really, this is too easy to game to worry the cynics - the site owners could log in and continue a few conversations for a bit to make the bad publicity go away.
If I was running this kind of operation I'd probably ensure some conversations continued for a couple of messages after users paid up, just to make sure they didn't cancel or file chargebacks. If I assume men preferred their hot women to pass the Turing test I could probably outsource the flirting to someone in the Philippines at $5 per hundred messages.
And if the messages are real, I'll be a monkey's uncle.