Contradiction with Proverbs 12:10
This verse emphasizes the righteous showing regard for the life of their animal, which contradicts the act of allowing swine to receive unclean spirits and perish.
Proverbs 12:10: A righteous [man] regardeth the life of his beast: but the tender mercies of the wicked [are] cruel. [tender...: or, bowels]
Contradiction with Genesis 1:26-28
These verses describe man's dominion over animals, suggesting a responsibility of care, which contradicts granting the request harming the swine.
Genesis 1:26-28: And God said, Let us make man in our image, after our likeness: and let them have dominion over the fish of the sea, and over the fowl of the air, and over the cattle, and over all the earth, and over every creeping thing that creepeth upon the earth.