Hi Tom,
Thanks for your response on this.
I have seen several credible websites state that canonical image URLs are not used by Google and should not be used, even on MOZ I have read this too I believe. Interested to know your source on this?
The use of our own self-hosted cdn to load images using multiple connections is following Google's image best practices - this is recommended across the web too. So not sure what the problem is you are highlighting there? The only thing that was a concern was the fact we are using a different domain entire, not the deployment of the self-hosted cdn.
The og:image and structured data image are using the primary domain, and again, that is following best practices.
Thanks