Fine, so when does he stand trial here?
I presume once the USA has made a case to the Supreme Court in the UK and lost. Then they can press the NCCU for full investigation and due UK legal process. Unfortunately for the USA such an offence under the Computer Misuse Act (1990) would be deemed 'unauthorised access to computer material' and subject to a maximum 12 months, but for a 1st offence it would far more likely to be a probation order, working in a library for 150 hours helping pensioners get online and a modest fine.