Ever had a remote user who uses a laptop outside of the company network and their cached credentials somehow do not work or have been lost from the cache? I recently faced this same issue and with a little advice from a colleague, I was able to successfully get the users credentials cached once again.
The way I was able to accomplish this was the fact that we had VPN setup, and since most companies have some sort of VPN for their users to access email and documents, we were able to use this to our advantage.
Essentially what I did was log onto the computer using the administrator cached credentials. Once in there I made sure the VPN connection was setup to point to my server at the main office, and I went ahead and logged in. Once in, I used a random application on the desktop (I think I used firefox), I right-clicked, and selected the run as option. When the dialogue came up, I used the end users credentials rather than my own. What this does is it will try to validate the user credentials with the domain controller because we are connected through the VPN.
Once this is done and the application opens, you can disconnect from the VPN, log off of the administrator account, and try logging on with the end user.
I was successful in my attempt and I hope you are too!