It's hard to tell from your picture, but it looks like a telephone line connector (RJ11), versus RJ45, is that correct? You can do a lot with wires, they don't necessarily need to be used for intended development. This looks like the previous owner was "commed-up" as a mobile comms outpost. Connections stay, equipment/cords leave when operator departs the vehicle, just one guess from many possibilities. Maybe you can make use of it, keep us posted.
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