Yes thats correct a neutral too. As well as a ground, and two hots. But the ground can be the conduit (metal) feeding the sub-panel. As in the case above the feed coming in at the top the “ground” has been cut. So it appears the panel is not grounded properly unless there is another grounding wire that the photo doesn’t show.
So the question remains is the panel grounded? It does not appear to be the case unless it is below what we see in the photo.