I had the same problem. My solution was to define the timeout constant for the cron job by adding this line in wp-config.php:
define('WP_CRON_LOCK_TIMEOUT', 60);
I added this before the line require_once(ABSPATH . 'wp-settings.php'); and it worked. By default this is set to 0.01 seconds, which to me it makes no sense. This line sets it to 60 seconds.