You say "to go and make a statement at the police station next week". That's not correct.
He does not have to say anything to the police if they question him, and he certainly does not have to make a formal statement.
I would not make any comment or statement until a formal allegation had been put to me, and I had time to make an informed decision on what to do, having taken proper advice if necessary.
If he "admits" guilt he is far more likely to face a charge than if he did not admit it. On the other hand if he is given the option to take a formal caution which involves accepting guilt, and he is willing to accept that and its consequences, rather than facing a formal charge in a court, then that might be a better way to resolve things.