A long time ago I repaired a Kimball player with the exhauster system
under the keyboard and, if I remember correctly, the player had the
equivalent of a "fast forward" button which would cut off the stack
vacuum and send it all to the roll motor, which would race the roll
past a section the listener didn't want to hear.

If this piano is so equipped, I think there are opportunities in the
design for it to be cross-tubed somehow, or for cross leaks to form
in the valve box under the keyboard.  Maybe the tracking supply tube
is hooked up to the "fast forward" nipple.

Also, if there is no "fast forward" feature, and the cutout for the
stack is controlled by a pouch and valve instead of a rod-controlled
sliding valve, maybe the tracking and cutout tubes are switched.

Hopefully, food for thought.
Tim Gautreaux