Possible to rebury a Fockea edulis?

[Angora]

I picked up a fun-looking but not-ID'd caudex plant for a few bucks, which I've now identified as a Fockea edulis. The caudex is a ball the size of a goose-egg, but I've since read that the caudex will stop growing once exposed to air. I've found info in one place saying that once the outside "hardens off" it won't continue growing even if reburied... can anyone here confirm this? I don't want to dump more material on it hoping it will continue to grow just for it to rot or be unhappy.