When you're infiltrating an anti-zombie hate group it's best to have a cover identity with a proper motive. Having zombies eat and turn your twin brother into a zombie and it just so happens that you have photographic proof of said zombie will help sell the cover. It also helps if that you have someone to vouch for your identity that the group you're infiltrating would know and/or respect. When your life may depend on the person you have vouching for you, it doesn't hurt if they're a quasi famous television star known for killing zombies on your program.