I read everything that was available at the time this happened and there is no weight & balance issue. He seat swapped with another passenger. Not saying he should have behaved the way he did, but I don't think the CC handled it all that well either. The pax he swapped with wasn't the same ethnicity and stated that the tasered pax did nothing wrong (other than refuse the CC direction to go back to his original seat).
I see all the flying lawyers are out and about.