[j4coh]

By novel, I mean if I ask a model to write some lyrics or code and it produces pre-existing code or lyrics, is it novel and legally safe to use because the pre-existing code or lyrics aren’t precisely encoded in a large enough model, and therefore legally not a reproduction just coincidentally identical.

[raggi]

No. I don't think "novelty" would be relevant in such a case. How much risk you have depends on many factors, including what you mean by "use". If you mean sell, and you're successful, you're at risk. That would be true even if it's not the same as other content but just similar. Copyright provides little to no protection from legal costs if someone is motivated to bring a case at you.