There aren't many professional TG users and the few who are aren't very active here, if at all.
So best you can get is a guess from experienced users which don't have render farms or do not use render managers.
If the path is empty, so only with a filename mentioned - like 'cache.gic' - then TG assumes the cache file is present in the same folder as where the .tgd is.
For other situations it's best to use complete path description, but I have no idea how that would work for a network drive.
My best guess is to put the .tgd file where the cache files are kept and remove the path to the .gic files in your .tgd.
Except for the filename itself of course.