How do I champion my pull request?

I submitted Add support for explicit control over model animations by markw65 · Pull Request #9339 · CesiumGS/cesium · GitHub a couple of weeks ago. According to the contributors documentation:

  • It is ultimately the responsibility of the pull request opener to get their changes merged. They should champion their code being merged and should bump the PR or @mention a specific developer if it is not getting the necessary attention.

I tried @mentioning people who reviewed a similar pull request in the past, but there’s no response at all on GitHub. I’ve just pushed a rebased version since a recent commit to caused a (trivial) conflict in that file.