why is this so confusing to so many umpires?

[CajunNewBlue]

Had a discussion during a umpire meeting with umpires from various associations (nothing like a meeting of the minds....lol) and this scenario was presented.
2-2 count on the batter (outs and runners dont matter) pitch is delivered legally and batter swings at it and it clearly hits the batters hands and NOT the bat... ball rolls fair. whats the call?
Now, being a softball umpire this is "clearly" spelled out in the rule book that this is a dead ball strike and being the third strike, batter is out. of course my answer brought up (surprisingly) considerable debate.
So I go home, break out the OBR, FED and PONY rule books and case plays and I cannot for the life of me find anything that spells this out as they do in the FED softball rulebook.
Now, I know common sense should dictate that it doesnt matter where the ball falls (fair/foul) as its a dead ball once it strikes the batter and its swung at... so its a strike.
So any rule/case play reference's would be greatly appreciated.