It does not sound as if the police have handled this matter very well. The most serious shortcoming, I would suggest, is the lengthy delay between the incident and their action. As you say, the matters would have been fresher in your mind had their enquiries been launched a little earlier.
Having said that, I would be very wary of the advice from �one of the greatest criminal minds in the UK� (aka Bewlay Bros). You have probably heard on countless occasions on the telly �It may harm your defence if you do not mention, when questioned, something you later rely on in court.� And indeed it may. Whilst you have a right to silence the law says (as Bewlay Bros�s great criminal mind should be aware) that the police, the CPS and, most importantly the Courts, can draw such conclusions as they think fit from your refusal to answer questions.
The police have a duty to investigate allegations. How they choose to do this may not always meet with everybody�s agreement, but one of the things they will almost certainly do if they intend that the matter proceeds to the CPS is to interview all parties. The results of those interviews will go to the CPS and form part of the evidence considered when deciding whether to prosecute.
You will have no idea what they will have discovered from other parties, or what they want you to clarify. The �prepared statement� routine will not help you one jot in convincing them of your innocence. Your statement is unlikely to be presented to court by the prosecution. The alternative is for you to read it in court in your defence and you will face cross examination on it.
As suggested by others, get a good solicitor (who will almost certainly not advise you to remain silent) and, under his guidance, co-operate fully with the police enquiries.