One reason why I would never slab with NGC. If you like that dime then my hats off to you. I'm amazed it was even graded with that big ugly finger print. My guess is when they received it you couldn't see the print but that's hard to imagine.
It's in an early slab. Probably before they imaged every coin they graded. I believe the coin changed in the slab over the years.
While I can appreciate a good conspiracy theory, in this case you are incorrect. This coin was probably slabbed in the early 90's, based on the slab. They didn't start imaging every coin (and posting the images) until a few years ago.