What speed was he traveling?
Could be any number of things. I wonder if the torque converter stayed in lockup and when he locked up the front wheels to stop the engine stalled?
But that's just one of many scenarios that could have happened.
If it's not a recurring problem, I wouldn't lose sleep over it.
My son had to hit the brakes hard today to avoid an accident and told me the car shuddered really bad than stalled out. Any idea as to what would cause this?