A perfect man who sins can very well die. Otherwise the mission of Jesus would have been no test of Loyality.
So if Jesus in his perfect state sinned only once - e.g. didnt accomplish his mission would be a sin (his mission was to be always LOYAL in the great issue and not to die as payment for Adam) - from this moment on he would have started growing old. So if he had not been loyal in just a single occasion he would have instantly began to grow old anyway and die a death of an unimportant forgotten cult leader.
But if he would have remained loyal and would not have sinned and so accomplished fathers mission of proving loyalty with bravour, he shouldn't have died at all and would now be father of many children with a beautiful woman. That was jesus plan.
Sadly the Romans wanted a harder test of loyality. They liked to test all crazy jews with thistlecrowns and torture and even tried lacerations and the test of cruzification on him to see if he was a real king.
Jesus had had other plans. He had not calculated that it would really come so far. He didnt want to die, but he wanted to stay loyal and live forever as perfect man on earth. He had to stay loyal so what could he do? He had to shoulder this roman punishment burden also.
If he fled and called his angel armee to help and free him from the Roman soldiers, he would have been a weakling but would he have been actually illoyal? Did his mission not only actually include Loyality or even loyality until death? Was it a loyality until death mission? Why should it have been a sin not accepting Roman death punishmentto? Would loyality really include paying the unique superman-price for Adams' guilt?
God would have certainly disfellowshipped him from divine companionship but later he would have given him a change to return e.g. as helper of the GB.
He would not have been better or more loyal than Adam. Jesus would have repented but had not commited any heavy sin - only that he didnt want to die and to accept a roman punishment - and so despite everything he would have lived for ever on earth in the end. He could even be a real king and turn over everything to make a paradise earth.
But he didnt want to be an unknown looser for his followers firstly and he knew that his mission included going back to heaven anyway, so he decided to die fast, so he also avoided further tests of loyality and further temptations as well as big sins and could give his followers the hope of resurrection. Was not that a good example? He only had to way 3 days and he would have given a better impression than Adam. (I must be crazy)