Thanks for the information and the time.
You do have the option to take out a private prosecution. It is not advisable.
Private prosecutions are very expensive and ultimately you have the same burden of proof and disclosure duties as the Crown.
You have to prove the case to a high standard. You have the burden of proof and the standard is to satisfy the court so that they are sure which is hard to do especially when the authorities have taken a view that it cannot be done.
Also, you have to appoint a disclosure officer at your cost.
Further, you run the risk that CPS will take over the prosecution and drop it.
Private prosecutions can be a good idea in circumstances where the authorities are failing on a wholesale scale; for instance women making false allegations of rape. Men can almost never get justice in those circumstances from the public authorities. Save for that type of circumstance though, it is a very dangerous action to bring.
Hope this helps. Please let me know if you need more information.