If she's going to lose her blood in 3 min, why not hasten that along? Another shot to the body would be even worse. Again, Henderson could have done much more. I think this is a game between Bauer and Henderson. Remember, Jack shot his wife in the knee. Problem is, Henderson never gave up his info- Jack did. Henderson now knows Jack's weakness, and I wouldn't be at all surprised if we see Henderson grab Kim and kill her.
In fact, I had forgotten that Jack had shot H's wife's knee--oppps above the knee, to be exact : > Jack's notion of kindness. I agree that is the template here. He even did it in the same day --in the mad rush that is 24.
I do dissent that if H shot Audrey, it may be too uncontrolled and that would mean he would lose the effect he was trying to accomplish. No telling what JB would do upon hearing a shot and realizing that A was hit. There is also the uncontrolled affect on her body.
BTW, it must be interesting to be part of the staff that writes the show. Apparently, it is up for consideration as to how or what is going to happen. That must be wild. All the ramifications!