One could further not disregard the probability that he had no control over the device at the one end of the scale, or that he had no disclosure from the courier/maker as to the intention of the device at the other end...
Agreed, it's quite possible the 'bomber' thought he was a courier - 'deliver this laptop to Mr. X, it's very important' and had no idea he was on a one-way trip.
As for the repairability of the aircraft - based on the photos I've seen it should be a straight forward repair, basically replace a couple skin panels and stringers. As Busbert notes, aluminum panels can be readily repaired and the industry has had lots of practice. Recall that the United 747 that lost the cargo door out of Honolulu suffered far worse damage yet was repaired and returned to service.