A random thought that occurs to me: if there is a CDN between the user and the LMS, or some sort of load-sharing so that several servers share a domain name, it would tend to break connections like that (especially if configured wrong). As I say, that’s a pure guess.
Justin: you can create a free account at cloud.scorm.com. It’s an LMS cloud service. If your company’s policy allows it, create an account there and see if you have the same problem with a different server.