Redirection Pass-Through Not Working

Hello. We are trying to use your plugin in order to add a pass-through for one of our media uploads.

Source URL: https://www.connectbooster.com/msps_ultimate_guide_2/
Target URL: https://www.connectbooster.com/wp-content/uploads/2021/03/MSPs_Ultimate_Guide_2021.pdf

However, when we set it up, we end up getting a 404 error for the pass-through when we go to the source URL. Any idea how to get this to properly pass through so they see the PDF content properly?

The page I need help with: [log in to see the link]