@noithatgooccho There are different ways of getting what you are calling a “local cache”. Though the solutions have different restrictions or requirements.
Install a normal FOG master node in that location (no connection to the other server), register all your local hosts in that new server (it’s own database), create image definitions and manually copy the image files over to that server. Every time the image on the pre-existing FOG server is changed you need to manually copy the image over again. But local hosts can also capture an image to that new FOG server in that location.
Install a FOG storage node in that location - which needs to be able to constantly contact your pre-existing FOG master node to query information from the central database. The image files will be replicated from the pre-existing master node to the new storage node once (every time the image changes) - no manual copying needed. The hosts in that location can pull (deploy) an image from that new storage node (local cache) in unicast mode. But be aware that hosts in that location can only upload/capture an image to the pre-existing master node, not to the local storage node.
So it depends on what you want to achieve.