The Holy Bible was compiled by the Catholic Church who has its authority to speak for God through the Keys give her by Jesus to St Peter. King James was not authorized by God to translate the Holy Bible and he certainly did not put the Holy Bible together.
When did God give Salam the Persian the authority to mess with the text of the koran? The original koran had no pronunciation marks and many interpretations of the original texts could be made; there were several different version at one time. Now if you say people had memorized the original text and so the koran was interpreted from the memories of others. What assurance do you have from God these peoples memories were correct; after all, we know how poor memories are.
Peter lost the key, when he ran away and abandoned Jesus. It was never found.