why is he in trouble for then ?
They wouldn’t have spent this much money and resources on just anyone.
If he was someone else who had a European Arrest Warrant outstanding for rape, the authorities would take it seriously. Our press are going to have a dim view of a foreign (alleged) rapist running around because the police couldn't be arsed.
Jumping bail to an embassy in Knightsbridge and talking to the media from the balcony isn't going to help them look the other way either.
Ignoring the specifics in this case, I'm assuming you know absolutely nothing about our legal system? Jumping bail is not taken lightly in most of the world.
Of course, now we know that there's been an US warrant on JA since at least Dec 2017