I would tend to agree that the rolls are for a piano, and not for
a music box, for the following reasons:

I stumbled across an article in "The Music Box" (Autumn 1966, Vol. 2,
No. 7, p. 362) on the subject of the Libellion, which is the only card
driven music box I've heard of (not disallowing that there were indeed
others).  The article states that "the music sheet is 9-3/4" with a
center row of 3/16" square drive holes at 3/16" spacing".  Also, it
played card books, not a roll.

The lowest bass note [in the photo image of the mystery roll] is repeated
so often, it looks to me like [it controls] a sustain pedal mechanism.
If it were playing an actual note, it would sound ominous.

Regards,

Eliyahu Shahar

 [ See the photo at http://mmd.foxtail.com/Pictures/index.html
 [ -- Robbie