However. If you chip the VW engine and tell your insurance Co your insurance will go through the roof. they might even refuse cover. If you do not tell them and they find out then there is a possibility you'll find yourself with no insurance and placed on the Facility which is REALLY expensive... not a high chance but a chance nonetheless.
Ontario needs an Insurance Co with a sense of humour...unlikely I think.
I'm not sure what kind of device you need to see if the ECU has been reflashed.
You can't find out with a VAG-COM for example. But I'm sure a more sophisticated diagnosis tool will be able to find discrepancies.
Then again, when the car is totalled I don't think the adjuster will bother to plug in a VW specific diagnosis tool in the OBD port.