With the spate of arrests under Operation Quest last year, AFAIK we have heard nothing in relation to prosecutions under that!
If you are not caught in bed with an escort while in a state of arousal or you blab your mouth off to the pigs, how can you possibly be prosecuted?
They may put pressure on the lady to inform, if she does, then you can have her called to your hearing and if she doesn't turn up, there's absolutely no case!