You didn't miss anything. Unfortunately this is an especially confusing bug: Dawn and Dusk copies show default stats, but actually (correctly) have buffs, keywords, and damage. So the Jinx copies were actually 8|4s.
This is fixed in 1.1. Sorry for the frustration! :(
So I saw a post yesterday taking about how their copied Zed's weren't buffed. Seeing your judgment not kill the other copied Jinxs makes me think it was only a visual bug.
Edit: I should elaborate a bit more, "exact copies" means exact. I know this from beta when I would frostbite whatever unit was about to be duped, creating a bunch of worthless 0 power ephimerals.
You nailed it!
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