Kim and Mikey may have to prove that Marko is real and that he made the statements in question
Defendants don't have to prove anything. It is up to the Plaintiff in a libel and defamation case to prove damages and prove that Kim and Mikey knew the information they were given is false. It will be a giant waste of money and time for Lloyd to pursue. Lloyd also suggested some sort of criminal complaint. Again, based on what? It is not a crime to hand over evidence to the police and ask for them to investigate. There is no such thing as a thought crime.