There's probably a solution, but the R&D, development, and other costs is probably not worth the hassle, especially if the TW wasn't supposed to upgrade. Maybe have the TW uninstall Office 2010, and reinstall Office 2007. Or, create
a VM with Office 2007, and use that when interacting with SharePoint.
(If it WAS an unauthorized installation of 2010, then just fire the teleworker and get one that doesn't alter the configuration of their machine without approval. :D )
Steve Clark, MCTS | Twin-Soft.com