My apologies, but this forum is peer-to-peer and not monitored by Xerox support officially.
I happen to be a 2nd level rep, and answer a lot of stuff here un-officially, but if you got through 2nd level to Engineering and they declined to fix it, there is no other avenue to use.
Your only option at that point is to do a FER (Feature Enhancement Request), which is still through calling Xerox, but instead of reporting the matter as broken, you are requesting a feature be added, and again, there would be no guarantee it would get implemented unless you actually paid them to develop the feature.
Probably cheaper and easier and certainly faster to switch to scanner from the device to an FTP server or SMB share which certainly will allow you to make the required change.