Christa,
Your medal, and John Auten, are indeed genuine. I also own a medal like the one you describe. It was released by the Grand Army of the Republic in South Bend as a tribute to John Auten, the first soldier from South Bend to die in the Civil War. However, he was not, as the medal states, the first soldier to die in the Civil War.
Private John Auten enlisted in the Union army on April 22nd 1861 in company I, 9th Indiana Infantry (3 month regiment.) He was killed at Bealington, Virginia on July 10th, 1861. Auten was later honored with a medal bearing his image, and a road in South Bend, Indiana, that bears his last name. Also the South Bend G.A.R. post #8 was named the Auten Post in his honor.
I'm not sure if you have ever heard of the website find a grave or not. In the past I posted a memorial for Auten. You can visit it at:
Or get on the find a grave website and type in John Auten. He is listed as private John Auten on the web page. Hope this helps,
Eric