Extract from the Road Traffic Act regarding action needed following an accidenmt:
(2)The driver of the motor vehicle must stop and, if required to do so by any person having reasonable grounds for so requiring, give his name and address and also the name and address of the owner and the identification marks of the vehicle.
(3) If for any reason the driver of the motor vehicle does not give his name and address under subsection (2) above, he must report the accident.
(4) A person who fails to comply with subsection (2) or (3) above is guilty of an offence.
(5) If, in a case where this section applies by virtue of subsection (1)(a) above, the driver of the vehicle does not at the time of the accident produce such a certificate of insurance or security, or other evidence, as is mentioned in section 165(2)(a) of this Act—
(a) to a constable, or
(b) to some person who, having reasonable grounds for so doing, has required him to produce it,
the driver must report the accident and produce such a certificate or other evidence.
It seems two offences have been committed. Firstly name and address details of the driver (and owner if different). Secondly insurance details have not been produced.
Your friend should contact the duty inspector at the local nick, present what information he has and ask the inspector what he proposes to do about these offences. If he gets no satisfactory answer he should contact the Borough Commander.