The plugin isn't be detected because JCH Optimize is compressing and minifying the page contents. Because of that, the scan of your HTML isn't detecting what we normally expect.
I'd recommend running Autotune and setting up JFBConnect with JCH Optimized disabled. Once things work as expected, then re-enable JCH Optimize and ensure nothing breaks. Many, many sites use JCH Optimize and JFBConnect together, but you still need to verify things as overly aggressive optimization settings can cause some unexpected behavior.
I hope that helps explain, but if you need anything else, just let me know.
Thanks,
Alex