I am no expert by any means, but could the wires be tapped into and a bypass loop configured so that when the device and wires were cut the circut would remain intact?
We all know about the bomb in the movies that will explode if the wires are cut but we are dealing real world. If the battery is severed from the detonator, what are the odds of the bomb exploding? How many bombs are really "tamper resistant"?