Exactly. The work was created quite some time ago. If there was indeed a remote control built in, how could it have "stayed alive" for such a long period of time? Regular batteries would have been depleted by now.
One time as a teenager I was messing with my father's hand-held film motion picture camera. Surprisingly it began running, upon checking dates it turns out that the batteries were over a decade old. It could explain why the shredding stopped halfway through the canvas. The batteries were Duracell's. or the whole thing was staged with a tight inner circle. This seems unlikely given his body of work.
9V powering the CDMA receiver and alkaline D cells powering the shredder. Alkaline have at least a 10- year shelf life.
I'm just hoping more of his art can go the same way. Also all that junk by Antony Gormley, Yves Klein and quite a few others.