You can re-run the installer / updater from the command line to check for any errors:
/usr/local/psa/admin/bin/modules/juggernaut/install.sh
/opt/psa/admin/bin/modules/juggernaut/install.sh
Wrong time on the server
Make sure that the date and time on the server is correct. The wrong date and time will cause the SSL certificate connections that the installer uses to fail. You can sync your server time using the command:
// sync the time
/usr/sbin/ntpdate -b -s time.nist.gov
// re-run the installer and check for errors
/usr/local/psa/admin/bin/modules/juggernaut/install.sh
You can run the uninstaller from the command line to completely remove the extension:
/usr/local/psa/bin/extension --uninstall juggernaut