Maybe the cable is to connect the Schmid to a PC? For developing or dumping purposes? Have you ever opened the console to see how this cable is wired inside?

First, it's obvious that the flaps are missing on top of the port. Second, also inside the port should be more plastic that's why it looks to small.

Looking at the picture I would say yes it's the same size. The connectors of the Schmid carts are small. But maybe you can try to plug a cart in?