Gorgeous! If you want to save them as intended, I suggest you try the soap welding technique to rescue them. Add moisture to the area with the separation, dry the larger flat (face) surface with a cloth. Then tightly wrap in plastic food wrap (very tightly), and place on a lined baking sheet & heat in a 200° oven for 10 minutes (with oven on), then remove to allow to cool, remaining tightly wrapped for at least a day. (also don't poke & prod)
For that last photo you linked, it looks like ash maybe part of the problem (actually it may be for all of them) & it looks like you might be able to just pop the circle right out because of shrinkage. This would be a good one to test the soap welding technique with.
I would wash the soda ash (if that's what it is) off of the circular center after popping it out, by dipping it in extremely hot water, dry it gently with a towel. Then score the outer edges of the circle with a sharp knife, just to give it a bit of a rough edge. Do the same with the inner circular edges on the main bar. Then get those wet. And with a soap paste (you can make yourself) spread out on all the surfaces that will touch, put the circle back in the hold. Gently wipe away any excess & tightly wrap in plastic wrap. The plastic wrap serves the purpose of clamps, holding the pieces tight while the heat 'activates' the 'paste' and creates the 'weld'.
Making soap paste or soap glue for this purpose is easy. Just get soap wet and create a thick lather on the surface of the soap, scrape some surface gumminess off the bar with a fingernail or other implement & work it into the scored surfaces and/or into any crevices you want to fill and 'glue' the pieces together using the tight plastic wrap around the entire bar of soap. Then proceed as instructed for soap welding (heat + time, etc.)
PS, when I did my soap welding experiment in 2019, which I pictured in the Welded Soap challenge thread, it was soap that was a about a year old, but had been wrapped in plastic wrap the entire time, so although saponified, it had not lost all water making it fairly easy to weld. If I remember correctly, I believe I heated my soap longer than 10 minutes; it may have been 20 minutes. But the bar of soap did not melt and did maintain its shape. I let the soap remain in the plastic wrap for probably about a day, not toughing it while it cooled. I highly recommend this process it really works.
See these links for more detail on the technique:
https://www.soapmakingforum.com/threads/smf-july-2020-challenge-welded-soap.79925/http://www.fromgracetoyou.com/creatingsoapart/chapter10.pdf
Of course the poppies would be lovely, too, and I'd love to see what you do next.
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