A state should be allowed to prove to its own satisfaction that the public records of another state are legitimate. They shouldn't be forced to take another person's word for it.
-PJ
The full faith and credit clause says just the opposite of what you said. If any state says a record is legitimate and official, that record will be accepted as legitimate and official in every other state.
One more time: “Full faith and credit shall be given in each state to the public acts, records, and judicial proceedings of every other state. And the Congress may by general laws prescribe the manner in which such acts, records, and proceedings shall be proved, and the effect thereof.”