Sounds like you were supplying power. That's unnecessary in this case. Just leave the battery in. The question is if you can reliably push video down a 5 mile

Sounds like you were supplying power. That's unnecessary in this case. Just leave the battery in. The question is if you can reliably push video down a 5 mile pair of copper wires and send control inputs back up. And the answer is yes, even for an unshielded twisted pair. With the right encoding and enough voltage, you can get GBits down that wire.