I never even considered asking AI, and I've got paid memberships to them, too. Our family has been collecting netsuke's for decades so I'm familiar with tagua. Because they're so small all the physical attempts, anything that needs pressure, has failed. We've got nothing small enough to manipulate them. Mineral oil has failed - the seams are so snug the oil just cannot soak into them. The temperature idea has merit. I'm going to wet a cloth and then freeze it and hold the nut in a way that the bottom of the egg sits in it, and then get a very hot wet cloth for the top half. Hopefully the opposing temperatures will facilitate the opening.
As they're from Japan that's a totally reasonable concept. Doesn't help though Your signature "This too shall pass" is a great quote from Colonel Sherman T. Potter [twice, once to Father Mulcahy, the other to Corporal Klinger]
My quote is actually from Attar of Nishapur, a ca 1200 poet and Sufi master, and it has been quoted ever since. It fits the character of Colonel Potter, so I understand they put it in the script.