Tidus, focus on saving Serenity first. Jack is a threat, yes, but Serenity is in the most immediate danger.
That being said, the shock from the vest is likely less lethal than the explosions that would have occurred. At the very least, Super Boy could try to rip it off before the electricity damages Serenity too much. Not the safest, but an option.
I don't know how Copper plating would stop the short circuit so won't bother with it.But if Super Boy can Freeze the bomb that might work, though I don't know how that would work with actual bombs in that case.
The only advantage of surprise that could be given is if Super Boy flies in at speed large enough to blow away the Tear Gas, thus giving him a visual, and using his super senses to perceive the reality around him fast enough to formulate a plan. He can think fast, I know that much, and thinking will get him far. But if the idea that Super Boy can think of something quickly too impossible for you, than there is one other thing that might work, depending on how you vest is made. It could simply be destroyed. Most bombs aren't so volatile that they could be triggered by just shooting them, at least not military grade stuff. Right now the only thing that could trigger the explosion is if Jack releases the trigger. If they can't reach the trigger they can reach the bomb, and remove that from the threat.