The isomalt got cloudy from humidity (it doesn’t take much). I am not very experienced with isomalt… but if you store the pieces in an air-tight container with a desiccant pouch they will stay clear.
I’m not sure if there is a way to reverse it, so hopefully someone with more experience will be able to help with that. I made a glass slipper out of isomalt and this happened to my first try. I tried to use my creme brulee torch to restore the clarity but the difference in temperature ended up cracking my piece.
I’ve heard that rubbing a little vegetable oil on the isomalt will help keep it from getting cloudy, but I’m not sure if it will reverse the cloudiness once it has happened. If you have enough isomalt to start over, if need be, it might not hurt just to try the veggie oil on these ones?