Determining whether a work violates a copyright requires holistic consideration of the similarity of the work to the copyrighted material, the purpose of the work, and the work’s impact on the copyright holder.

There is not an algorithm for this, cases are decided on by people.

There are algorithms that could detect obvious violations of copyright, such as the one you suggest which looks for exact matches to copyrighted material. However, there are many potential outputs, or patterns of output, which would be copyright violation and would not be caught by this trivial test.

Probably not until they pay him a hefty copyright fee.