After contacting Sitefinity Support, I was informed of the following:
The error message stating that LibraryImagesBackend can't be found is due to the fact that this view has been replaced after Sitefinity 6.0 and is no longer in use. The site must have started to experience this after upgrade passing through Sitefinity 6.0.
To resolve the error, force the upgrade to run again by making the below configuration change in App_Data\Sitefinity\Configuration folder in SystemConfig.config:
After restarting my site to trigger the upgrade, I could view my Images once again!