Ever found a 'dummy' bass row on an 18-bass accordion?

I recently purchased an 18-bass, Zon-Rio accordion, kid size. The top
bass row appeared frozen and a couple of buttons were pushed in.

To my suprise, when I opened the back panel, it looked like the top
row of basses was a 'dummy' row.. the buttons left looked glued in,
and there were no extra wires in the back at all, nor any type of
place where an extra set of bass wires would have been anchored. In
other words.. was it a 12-bass with a dummy row? Have you ever run
into or heard of the like? It was a puzzle to me and to my accordion
teacher who has been fixing accordions for years. He'd never run into
a 'dummy row' before.