Alverto barely escaped death that day; even Aurora would have been lost.
Although he can borrow the strength of the higher being and can use it to do various things, even that can't help him fight against someone as strong as Ashtel.
He had lost nearly all of his subordinates and comrades in that sudden attack; he barely had a few minutes to save himself and Aurora.
If he had tried to take his subordinates away together with him, Ashtel would have easily noticed the problem, and he would have not stopped chasing them till the end.
That way no one would have made it out alive.
He succeeded in faking his death because of Neo's help and because of the sacrifice of all of his subordinates.
With everything that he had earned with decades of effort gone, he had no other choice but to return to the demon palace with Aurora to lay low for a while.
He was worried that even with the perfect deception and the sacrifice of his subordinates, Ashtel might notice something.
