To find this code, it will be either in the PageWrapper directly, or in a reusable that the PageWrapper is using. First, find out which PageWrapper your TeamRaiser event is using.
  1. Navigate to Setup > Page Wrapper Editor
  2. Enter the name of the wrapper in the search box
  3. Click Search
  4. Click Manage Versions under the Actions column
  5. Click Copy under the Actions column on the Active version
  6. Change the name if desired
  7. Click Copy
  8. On the copy you just made, click Edit under the Actions column
  9. Select Meta Tags
  10. Scroll down to the Additional HTML Tags for HEAD Element
The code will either be populated outright there, or you will have a line of code for an s-tag which should reference the name of the PageBuilder page being used. If there is a PageBuilder page named, navigate to it under Content > PageBuilder to update the og:image code.