Here is Dr. Houseleaks reponse:
Chris, Interesting. When I first looked at them, I just thought they were leaves and am still not convinced they are chicks. You may be right about that, but it is hard to tell from the pictures.
I would suggest you make sure that some of the green is in contact with the ground and watch them closely. A second alternative is to put the pot they are in in a closed clear plastic bag. If you do this you need to make sure they they are not exposed to direct sun light and make sure that the potting mix is neither too wet nor too dry. As you are an experienced grower, you should be able to judge. Perhaps a window indoors that gets bright light but no sun. The idea is to give them a stable, healthy, protected environment.
Perhaps a local company is able to do tissue culture and might be willing to help preserve an unusual plant? A local college with a biology department? If it is genetic, you would want to preserve/propagate the hen as well as the chick.
Keep all of the chicks from the hen and propagate them, even the ones that look normal. If the trait is genetic, then the normal chicks might show the trait later in life or in their chicks as some point.
If the fasciated "chicks" don't survive, then you need to concentrate on propagating the hen. If it was me and no professional help was available, I would do surgery this year to propagate the hen, regardless of the state of the chicks.
It's a risk. It doesn't always work, but I would dig up and divide the hen by cutting it in half vertically (carefully), apply a fungicide and dry a day or two, then plant each half. I would try to make the cut go very close to the growing tip of the hen. Keep them growing in the house under bright light and divide again once they are big enough. The divisions like this will often produce multiple plants from each piece, but sometimes the pieces can die. It can also depend on the size of the hen, as well as the variety of semp. I have also successfully used this method to save a hen that has started crowning for blooming, but it is very iffy for that. Think of it as vegetatively reproducing the hen, sort of like we do with heuffelii.
Why is it a risk? Well, beyond the cutting risks, there is a slight chance that the hen might survive after blooming or never bloom. But I think that is very unlikely. There is also the chance that the hen would not be able to properly generate new plants or regenerate itself normally. (but this is also why you are trying to propagate vegetatively.) Also consider that what you are seeing as "chicks" just might be fasciate flower spikes, in which case the hen may be getting ready to die.
Lot's of variables here. A lot also depends on how important it is to you to keep these going and how much expense and effort you are willing to undertake.
Oh, one more thing. If they are fasciated chicks, we don't know what the adult plants could look like! Very interesting possibilities there. Keep in mind that this could also be caused by a virus or some other environmental condition as well.
All these possibilities make this a fun project for you and it should be a worthwhile learning experience, regardless of outcome. Good luck!!
Lynn, I would put as much of the plant (the green plant) in direct contact with the ground as I could.