Unflagging a node with Rules Scheduler
I have figured this out myself.  Please refer to Comment #5 in Issue 2094541 for the answer, located at the following link:
https://drupal.org/node/2094541#comment-7955705
Here is what it says:

Finally, figured this out! The problem is, we're not supplying the required parameters to the Rules component. If you have given it only 'node' as the parameter, then, when you add the action to 'Unflag a Node', you must give the 'User on whose behalf to flag' a data selector such as 'node:author'. You can't do something like 'site:current-user' because that parameter is not available to the component when run through Cron.
Once you give it the required parameters, it should unflag the node through Cron.