Hello, I am a solicitor with 20 years experience. I will try to help you with this.
What you should do is contact a specialist criminal solicitor and explain the situation fully to him and we will be able to advise you what to do and ho to minimise the consequences to you. You are in a high risk situation and run the risk of a prison sentence. Contacting a solicitor now may help you to avoid that. If you are i receipt of benefit or on a low income you will be entitled to free help under the legal aid scheme. There is little point in me telling you more than this on this forum when you need to instruct a solicitor in the usual face to face way.
Plea bargains are a bit of a myth in the English criminal system. If there is a deal to be done it needs to be made by a solicitor. If the company is engaged in illegal activities will they report you to the police? They may need to produce accounts to prove the case and just perhaps be reluctant to hand over accounts to the police. You can use this link to try to find a solicitor http://solicitors.lawsociety.org.uk/
I would be grateful if you would please rate my service as I will not get paid for helping you if you do not.