I really can't see how they can ever allow tries like that... The ball is lost... he has no control, he certainly isn't holding it and if that wasn't over the try line it would have been called a knock on... On the same note, if he did that on his own in-goal area then the other team grounded it afterwards would it be benefit of the doubt the other way (as in he didn't ground it so the other side gets a try)?
The NRL isn't so lacking in tries that they have to allow shit like that to be considered worthy of even benefit of the doubt...