Who was the original writer of The Hobbit before J.R.R Tolkien?
Tolkien was translating a manuscript he had 'acquired' through sources unknown. The original writer was, of course, Bilbo Baggins, Esq.
Who was the original writer of the oompa loompa song from the movie Charlie and the Chocolate Factory?
They certainly did meet and were friends. They often read their books to each other as they were working on them. They meet regularly with a small group in 'The Eagle and Child' a pub. They called themselves The Inklings. it was Tolkien that was instrumental in getting Lewis to become a Christian, and Lewis became a very respected Christian writer.
He was a soldier in the First World War. He then worked on the Oxford English Dictionary before becoming a University Professor. He was also of course a writer and he published scholarly works related to his academic study of Anglo Saxon and Middle English poetry as well as his famous fictional work such as "The Hobbit" and "Lord of the Rings" .
For copyright claim. While a person is writing a book or composing they need to register the rough draft. This provides the writer a right of first claim because of the date if another person tries to publish the manuscript before the original writer does. Note: Things do happen. Manuscripts get misplaced, lost and stolen.