As far as your ticket goes, the charging company will need to prove you were on their property.
http://www.OHTA.ca OR http://www.OntarioTrafficAct.com
-Also I find it a little odd that you never got a "Notice of Impending Conviction" normally the city will send you a letter warning you that you have an out standing ticket that is over 15 days old and give you an additional 15 days to either pay it or book a court date. It is unfortunate that you never got one of these as they are a lot less difficult to deal with than a "Notice of Fine and Due Date."
- However since you have received a "Notice of Fine and Due date" it means you have already been convicted and you will need to petition a Justice of the Peace to re-open your case. Assuming the JP grants your request to reopen you can then request disclosure and see what evidence the prosecution has against you. This should get you a copy of the original ticket and a copy of the ticketing officers notes. Once you have those you can check for errors. For instance if the officer's notes say he ticketed a red Honda and you drive a blue Ford then you can use that to show that the officer made a mistake and wrote down the wrong plate number on the ticket. If you find an error like that you can talk to the prosecutor and there is a good chance that they will withdraw the charge, if they don't withdraw the charge you can bring the issue up at trial. I understand your frustration as even though you haven't done anything wrong you are still going to have to make several trips to the court house to get this thing sorted out.
These kind of mistakes are relatively rare but they do happen. Unfortunately in your case there seem to have been two mistakes, the issuing of an incorrect ticket and the failure to send you a notice of impending conviction, which possibly could have been dealt with without having to go to court. Unfortunately at this point I can see what you mean about the lost pay from having to make several court appearances not being worth it to fight a parking ticket that won't have any impact on insurance.