RPM Fusion is near 10 years old
10 years ago, one of the internal root Certificate Authority was generated for the project. The infra wasn't production ready yet, but few months later there was support for Fedora 8. One of the earlier message from the developers mailing list.
At that time, the idea to form a community shaped against Fedora was to bring people to work together on the same complementary repository for the distribution. Remember how Fedora started ? So this is still one root of the project.