They could have been hit by lightening. A tree might have falled on them. His wife might have had a brain tumor and suddenly had the urge to throw the child into the crocs mouth after Irwin handed the child to her. A huge meteor could have fallen on everyone there and killed them.
It's also possible that Steve Irwin had planned on driving somewhere with the child and that they both would have died in a car accident except that Irwin decided to feed the croc with the child.
The bottom line is that nothing happened. So what's the big deal.
If this thing with Steve Irwin is so fantastic when nothing happened then Tom Hamilton should be thrown in jail for letting his daughter surf around sharks. /sarcasm off
This may be a bit of a stretch, but I'm sure you get my point.