The FBI has a system to decide whether people will be charged for having classified documents. Intent is a huge factor. Both Pence and Biden had them sitting around. They did not know they had them until they did a search. They obviously had no intent to use them for anything. If they lie about it, that is a red flag. If they had huge amounts of documents that is a cause for further investigation. If they hid them or try to keep them, they will be prosecuted. If they immediately return them, it mitigates the problem.
Biden and Pence did the right thing. We all know who did not.
Biden does not have a scandal.