"Maybe the other keyboard belonged to the Sons of Champlin, who opened."
Hadn't thought of this, but it's the most likely explanation. I believe the Sons used a Hammond B-3? Listening to the surviving portions of 10/24 and 10/26, there is also no trace of Pigpen on organ - just TC on his Vox. So it seems the Sons' crew may just have left their keyboard out. (Possibly Pigpen COULD have played on it if he'd wanted to...) I'll sadly toss out the two-keyboards theory! That still leaves the mystery of Lesh & McNally's statements that Pigpen's organ was repossessed from the stage in fall '69. My guess is that Lesh is remembering the same incident that Constanten refers to, but assigned it to the wrong year - it only happened in fall '68.
