Okay, that's what is written on the Guardian, is bla-bla, it does not say how high the punishment should be if you book a hooker whose status you do not know. If their status is not immediately obvious, it will be hard to give you the death penalty. joke aside, even condemning one to the 1000 quid penalty will not be easy. ( get a decent lawyer )
If the judiciary were so serious with that matter, they would just need to watch sides like Vivastreet, AW and, and .. or ban them.. anyway
..as I have already written, marry and be faithful, then you are secure 
That's an old article and The Guardian has run articles, of all opinions, since then - if you take the blinkers off.
You're punting in Luton, a place avoided by most WGs, so what are the chances of any the EE WGs being there of their own free will?
Here's what you should know - from the CPS.
External Link/Members Only
Specifically -
Paying for Sexual Services
Relevant LawSection 53A of the Sexual Offences Act 2003, inserted by Section 14 of the Policing and Crime Act 2009, creates a summary-only offence of paying for the sexual services of a prostitute subjected to force, etc.
You can read the rest, about knowledge by the punter, sentencing, etc., from the link. Basically, it doesn't matter if the punter knows or suspects violence, coercion, trafficking, or not.