Fatal PHP error on update to 2.2.1 (500)

When my site auto-updated, I got a 500 error. PHP errors:

PHP Warning: require_once(/opt/sites/foo/bar/wp-content/plugins/molongui-authorship/fw/includes/fw-class-compatibility.php): failed to open stream: No such file or directory in /opt/sites/foo/bar/wp-content/plugins/molongui-authorship/molongui-authorship.php on line 82 
Warning: require_once(/opt/sites/foo/bar/wp-content/plugins/molongui-authorship/fw/includes/fw-class-compatibility.php): failed to open stream: No such file or directory in /opt/sites/foo/bar/wp-content/plugins/molongui-authorship/molongui-authorship.php on line 82 
PHP Fatal error: require_once(): Failed opening required '/opt/sites/foo/bar/wp-content/plugins/molongui-authorship/fw/includes/fw-class-compatibility.php' (include_path='.:/usr/local/php7.0/lib/php') in /opt/sites/foo/bar/wp-content/plugins/molongui-authorship/molongui-authorship.php on line 82 
Fatal error: require_once(): Failed opening required '/opt/sites/foo/bar/wp-content/plugins/molongui-authorship/fw/includes/fw-class-compatibility.php' (include_path='.:/usr/local/php7.0/lib/php') in /opt/sites/foo/bar/wp-content/plugins/molongui-authorship/molongui-authorship.php on line 82

This is on wordpress.com btw. I got the error messages from support, so I don’t have ongoing access to logs. I can give environment data if that’s helpful.