So the caution for speeding is meaningless right now since he did not issue you a ticket. Your trial will be for the fail to stop at red light which is all you should be worried about right now.
Of course the officer has 6 months to charge you for speeding from the date of the offence so if it has been less than 6 months (on Sept 28) then there is a chance that the officer could decide to charge you with speeding because you took the fail to stop to court. If it's been more than 6 months then you do not need to worry about the speeding thing at all.
You should go to the trial for sure. The prosecutor will probably meet with you before the trial and may or may not offer some kind of plea deal. Depending on your confidence to represent yourself, you may want to consider taking any offered plea.
So looking at the notes, I have these questions:
Was it night or day?
What was traffic like?
Are there any hills or bends in the road?
Is it possible the officer lost sight of the original car and mistook yours?
I think the officer says it took him 2.5 to 3km's before he was able to get to you to pull you over, so there had to be some distance between the vehicles.
Right after the officer gets up to testify, you will have a chance to cross examine him. This is the most important part of your whole trial. This is NOT the time to tell your side of the story, but it is the time to try and bring reasonable doubt to officers testimony by questioning him about day/night, traffic conditions, distance between vehicles, road type, visibility, losing sight of the vehicle, etc.
Your side of the story ... So remember not to testify against yourself, meaning:
Do NOT testify (do not take witness stand) or admit to anything if you know you did not stop. However if you believe that you DID come to a full stop, then by all means you should testify and give your side of the story.
If you plan to represent yourself, you should read this:
http://www.ontariohighwaytrafficact.com/topic7039.html and this:
http://www.ontariohighwaytrafficact.com/topic7032.html