The same argument could be made about any wrestling move performed, all it takes is a tiny bit of miscalculation on either sides part and you've got an injury. For whatever reason Sting just didnt brace himself properly when he landed, I didn't see any error on Seth Rollins part as far as his execution of the move, the only blame I can give Seth is that he did it a second time, I don't know if he just thought Sting was selling the move or maybe there was some miscommunication or no communication at all, but I would think that Seth Rollins is good enough in the ring to be able to read his opponent because Sting lost alot of momentum after that first one, it was pretty apparent watching it on TV that something was wrong. Any guy that has ever been in the ring, or even played sports period will tell you "your always one match, one game, one competition away from injury" its just the nature of anything physical. Does that mean you ban the move? I don't think so because it opens up a lot of grey area, well if we the buckle bomb, shouldn't we have to ban the powerbomb as well? So no I think you make sure your opponent knows how to take the move properly, make sure whoever is doing the move knows how to execute it properly and maybe limit its usage, instead of it being a regular in match move, why not have Seth Rollins use it as the precursor to the pedigree.