An update:
The complaint to the Police Commissioner didn't get far. "As the police are investigating the Commissioner doesn't think it is appropriate..etc." But I shall now get back to him in the light of recent contact with the police.
In brief, so far as the police are concerned, I have spoken with the investigating inspector, who has accepted somethings went wrong in the process, which she is going to address and update me in due course.
The first thing that went wrong was the officer who reviewed the original uploaded footage didn't pass the footage to the investigating officer, neither does she know how it could be, as so far as she is aware, there is no facility to do this. She is going to speak with the reviewing officer about this.
Next was the investigating officer, coming to a decision the insurance companies would sort it out, based upon my statement and him contacting me about injuries, without seeing the camera footage. Apparently if you are injured, it is treated under a different Section of the RTA. If there is an injury or death, prosecution is more likely. - I know there are some one here who would take issue with the last comment, as do I, having been previously been hit and injured and no action was taken.
Next was the investigating officer not being aware of the time limits for a NIP to be issued and ensuring his investigation was completed in sufficient time.
Then there was the conversation I had with the investigating officer at my house. It was not within his remit to discuss the driver going on an awareness course. Irrespective of whether a prosecution or DAC was to take place, the police had to be satisfied that they could prosecute in the event of the driver failing to attend the DAC or not engaging with it. So my initial statement, as detailed as it was, would have had to be rewritten and this should have taken place at the police station.
Finally, it was not surprising the investigating officer's recommendation for a DAC had been rejected, a) because the time limit for a NIP had been exceeded and b) my statement needed to have been rewritten to a prosecution standard.
The investigating officer is to be spoken to.
The inspector agreed the driver should have been prosecuted, but we are where we are. From the notes by the investigating officer, she is of the opinion that the driver had a moment of bad judgement, rather than someone who is malicious towards cyclists. As the driver had already agreed to go on a DAC, she is going to try again to get the driver on a DAC, but in circumstances which are outside the normal. If the driver fails to attend, there is nothing the police can do, but she thinks the driver would benefit from it.
If she cannot get the driver on a DAC, or she refuses to go on one, then the investigating officer and one of his seniors will visit the driver and show her the footage and explain in detail what could have happened etc.
Given the time which has elapsed, probably the best I could hope for.
I did say to her that it felt like cyclists were fair game for motorists and were were not being protected by the police. It may of course have been her defusing the conversation, but she agreed, claiming her partner had been hit when cycling, but the police could only work within the laws.