To prove intent, you'd need to be inside the mind of Packer at the time... Which you can never do. Or you can prove that it was premeditated with evidence that he had planned it days/weeks/months before hand.
So to say it's attempted murder is fundamentally wrong because you can't know for 100% certain that it was his intent to kill him. Any argument to say it was is just opinion and holds absolutely no weight whatsoever. You may say "Well obviously he meant to kill him, he stomped on his head" which is fine, but you need to understand that is YOUR opinion which doesn't make it fact. Unless you could be inside his head at the time of the incident, which you can't, you cannot say, with 100% certainty, that it was his intent to kill him.