tl:dr - The fileshare used for restoring from image must have the "-img" directory immediately within it.
This is for my own personal "the next time I need to do this" notes, but may it serve the internet at large...
Clonezilla offers a very straightforward means for backing up a disk over the network and saving the disk as an image file. What is never mentioned during the process, however, is what is needed to restore that image back to a disk.
Fortunately https://www.thomas-krenn.com/en/wiki/Restoring_a_Clonzilla_Image has the answer.
In general, the secret is this: The fileshare you attach to via Samba must point to the "img" directory created during the Clonezilla backup. Otherwise, it will not be detected, and you will never see any options to restore to disk.
Example: Let's say you do a backup to image file. You choose SAMBA. Server is 192.168.1.5. Directory is /mydirectory/mybackup. Image file is 2016-01-01-01-img. The backup runs. On the destination server, you find the directory /mydirectory/mybackup and within it is a directory 2016-01-01-img and within that directory is the actual data files.
If you turned around and tried to do a restore using that same information, you will NEVER come across any options to "restore". Never. Why? Because not mentioned at any time during the backup process is that in order to do a restore, the fileshare must have the "-img" directory immediately within it.
So, in our example above, I created a new "restore" SAMBA share which uses /directory/mydirectory/mybackup as the path. If I browse to \\192.168.1.1\restore from a Windows workstation, I see a directory "2016-01-01-img" immediately within. Good, that will work.
Now, when I fire up Clonezilla, I pick server 192.168.1.1., path "/restore", I then see all these options to work with "2016-01-01-img" and restoretodisk and life is good thereafter.
Clonezilla is awesome; don't get me wrong. I do wish that they explained this restore directory structure requirement up-front during the backup process, though. Now you know.