Checking success for a function that can return wp_error
$Result = wp_schedule_event( ##### );
if (is_wp_error($Result))
echo "wp_schedule_event error: " . $Result->get_error_message();
else if ($Result === True)
echo "wp_schedule_event success";
else
echo "wp_schedule_event something unknown went wrong";
Feel free to comment if you can add help to this page or point out issues and solutions you have found. I do not provide support on this site, if you need help with a problem head over to stack overflow.