The only problem with this scenario is only the courts could declare that the votes were fraudelent or invalid. No court has done so. Pence cannot just declare the votes fraudelent on his own.
Courts have no role in the US Constitution on events of January 6th. It is entirely up to the people closest to voter’s desires which is state legislatures. Framers purposely and effectively excluded the judiciary for events on January 6th.
Can you show me where in US Constitution it says the presiding officer on January 6th has no power to decide which slate of electors is valid?