While both the appeal to pity fallacy and red herring fallacy can serve as a distraction from the original discussion topic, they are distinct fallacies. More specifically:
Appeal to pity fallacy attempts to evoke feelings of sympathy, pity, or guilt in an audience, so that they accept the speaker’s conclusion as truthful.
Red herring fallacy attempts to introduce an irrelevant piece of information that diverts the audience’s attention to a different topic.
Both fallacies can be used as a tool of deception. However, they operate differently and serve distinct purposes in arguments.