It appears that the content links are still good. Users can click on the container and download the content to their computers but they can no longer view them in the container.
I ended up correcting the problem by closing the file on the server and then downloading it from the admin panel. When you do this it merges all of the externally stored container files into a single .fmp12 file.
I did not have to re-upload the file after I downloaded it. I could be wrong but it appears that just forcing it to go through the download process made it do something to restore all of the container images so they could be previewed again.