It will probably not work but I will try anyway.
And.... should that fail.... I'll start a tradition of filling walnut shells with random candies and tiny toys for my nephew. ^_^
I've had reasonably good luck cracking these things.
I baked the walnuts at 250 for 25 minutes. A few cracked open on their own. Some favorably, some not.
More often than not, they break cleanly. Get a thin knife in and tap lightly on the seams a few times. I've only had one break so badly that I had to throw it away.
The one on the right... I was testing a theory. I think it is more trouble than it is worth. That one is formed of six earring hooks with beads on them. I curled the tips in to loops and threaded them on rings alternating with beads. The loop on top to hang it from is not centered and I don't think I could get it that way if I tried. >_< ~grumble~ fun idea... but I just don't have the patience to do many of them. It was a real pain. (but it's kinda cute, anyway)