The snake was punished for enticing Eve. This seems like it was an AS IF the snake ate the forbidden fruit. For example, a person who robs the bank and the person in the get-away-car are equally responsible for the bank robbery. As for animals eating meat, Genesis does not record that they consumed meat.
Genesis 6:12 reads: ki hishchit khol basar et darkho al haaretz (G-d
decided to destroy the world with a flood) for all flesh corrupted
their way upon the earth.”
What is the meaning that humans and animals became corrupted? Bible scholar and rabbi Arnold Ehrlich, author of Mikra Kipheshuto, “The Bible Literally,” wrote that humans and animals began to eat meat. For example, fish eat worms. In the Garden Adam and Eve only ate fruits and vegetables. But since humans desired meat, G-d "allowed" Noah to consume meat, but the prophet Isaiah foresaw a time when the lion would lie with the lamb, a time when humans and animals would no longer consume meat.