In the end, the answer was simple:
mount -o noowners -v- t smbfs //domain;user:pass@sharename mountpoint
will mount the smb share for all users, bypassing the sudo the script runs under, and enabling access to the share by the FDE Installation package.
However, this foray into shell scripting is getting deeper and deeper as I try to automate my Mac setup more and more. My current favorite utility? Bwana - a great utility for viewing man pages in Safari.
