Hi Paul,
I have looked at the URL you provided.
This is the image that is set as og:image which Linkedin will first look for:
macleanengineering.com/images/support/ri...ia-975-EV-Bolter.jpg
When pulling up the page in the (new) linkedin inspector, you can see that Linkedin takes that same image, so it appears it is working correct.
www.linkedin.com/post-inspector/inspect/...erground-environment
On the post inspector you can see where it finds the image (og:image metatag) and that this is indeed the correct one.
Note that the (new) linkedin post inspector refreshes the linkedin cache and fetches everything fresh from the provided url.