Register a new XLX Reflector
XLX is a slightly unusual beast, in as much as there isn't exactly a config file for it, some of the options compiled in, and some features (like call-home) are built into the dashboard.
You can obtain your own XLX from this Git Repo. In order to ensure that your XLX is listed in the Pi-Star host files, just make sure that you have the call-home feature enabled in the dashboard, this will automatically list your XLX with the rest of the XLX network, and in-turn will cause your XLX to be listed in the Pi-Star Host files too. Once the call home process has been completed, it can take a little while for the new XLX to show up, so please give the process 24h to verify that it is, or is not showing up. If your XLX is now showing in the list of other XLX servers from any other XLX, get that working first.
For a hint on where to look, see Dashboard V1 or Dashboard V2.