In case anyone else finds themselves in a similar situation, if File Manager HD doesn't show the files you need, try returning to the long list of all currently installed Android applications, and click on ES File Explorer.
Close the update request and explanation about controlling the app if they're displayed, then expand the LOCAL menu on the left. Click on the Device / entry and then the SYSTEM folder. From here, select the Preinstall folder, and you should find the apps that were originally on your device can be reinstalled.