You do have a 12-v battery. It's just not pb-acid. You'll have to fork over $19 to the Kia Service Website
for 3 days of access to the electrical schematics to find something to tap into. Alternately, you could measure for voltage at the connector you found. If it goes hot when the lights go on, you're golden. The high-voltage lines are orange. Stay clear of any orange wires.