That would be one heck of a mule (3C obverse, half dime reverse), never mind the vastly different amount of wear on the two faces. Or, more likely, somebody at NGC fat-fingered the image references.
Ha! Not only does it not look like an AU58, it doesn't look like a 3-cent silver! How weird. I never noticed they had the wrong reverse image (the wrong coin entirely!) in the slabshots on the cert page. I always just paid attention to the larger Photovision images. Thanks for pointing that out. I just reported it to NGC. I guess they figured, "Oh well, it's a small silver coin with an O-mintmark. Close enough! 3-cent silver? Half dime? Eh, whatever!"