I'm just looking around the c-panel and found a number of these entries in the error log:
[29-Mar-2016 00:51:27 UTC] PHP Warning: require_once(/home2/gridless/public_html/wp-content/plugins/jetpack/class.jetpack-sync.php): failed to open stream: No such file or directory in /home2/gridless/public_html/wp-content/plugins/jetpack/jetpack.php on line 37
[29-Mar-2016 00:51:27 UTC] PHP Fatal error: require_once(): Failed opening required '/home2/gridless/public_html/wp-content/plugins/jetpack/class.jetpack-sync.php' (include_path='.:/usr/php/54/usr/lib64:/usr/php/54/usr/share/pear') in /home2/gridless/public_html/wp-content/plugins/jetpack/jetpack.php on line 37
[29-Mar-2016 06:20:23 UTC] PHP Warning: require_once(/home2/gridless/public_html/wp-content/plugins/jetpack/functions.gallery.php): failed to open stream: No such file or directory in /home2/gridless/public_html/wp-content/plugins/jetpack/jetpack.php on line 49
[29-Mar-2016 06:20:23 UTC] PHP Fatal error: require_once(): Failed opening required '/home2/gridless/public_html/wp-content/plugins/jetpack/functions.gallery.php' (include_path='.:/usr/php/54/usr/lib64:/usr/php/54/usr/share/pear') in /home2/gridless/public_html/wp-content/plugins/jetpack/jetpack.php on line 49
I checked, and these files were indeed missing. I copied them from the backup folder but still no luck.