I’d recommend taking a look at the ftp server configuration on the NAS. It seems, to me, that the configuration of FTP is just making the FOG user’s Home directory as /volume1, so when the first login happens, the root of it is the root of volume1 which leads you to /images /images/dev.
Maybe, if you can find the configuration and make the home for the fog user the / of the drive, this can be resolved. I can code in this stuff as well, but don’t think that that’s the solution proper. It’s much easier to make one change to a configuration file rather than make code changes to the core of how fog operates. While it can be done autonomously, it’s not the norm.
As we found out earlier, you can’t nfs share an nfs shared volume. My solution was to use another mounting medium such as ceph or glusterfs, but don’t know if this would work in the case of NAS’.