If you rely on TWAIN then you should have the driver package on at least a few PC's there already, just copy the C:\Xerox folder from a working PC via USB or LAN and install on the ones that don't have it. Or get it from the CD ROM that came with the printer.
Or switch to USB scan, or SMB scan, or FTP scan, or scan to email.
If you require to get them only from Xerox.com, grab them in the off hours, because the site has been working fine outside of the 9-5PM times in North America. Enough so that I backed up the files, and direct links to them, for the print drivers and latest firmwares of about 25 models last night about 7PM EST.
I've been waiting patiently for a week now to be able to access the driver page/downloads for my copier but it is really starting to affect our business and I need these drivers.
Is there any other file repository available where I could find these drivers?