"A federal court in Indiana has rejected atheists’ requests to preside at wedding ceremonies..."

"... saying only clergy or public officials are licensed to solemnize marriages."

A lawsuit filed by the Indiana chapter of the Center for Inquiry argued that an Indiana law that requires marriages to be “solemnized” — made official by signing a marriage license — only by clergy, judges, mayors or local government clerks — violates the Constitution.

If you don't want a religious officiant, you're forced to use a government official. In Indiana.

May I suggest Colorado, where you can be your own officiant?