You should know that the statistical models don’t contain copies of their training data. During training, the data is used just to give a bump to the numbers in the model. This is all in service of getting LLMs to generate cohesive text that is original and doesn’t occur in their training sets. It’s also very hard if not impossible to get them to quote back copyrighted source material to you verbatim. If they’re going with the copying angle, this is going to be an uphill battle for them.