A few years ago my Ariocarpus 'Cauliflower King' from Thailand began to rot. I saw it very late and could save only two tubercles.
I grafted them on Ferocactus glaucescens. About one year after grafting, offsets began to grow.
One of them made an offset from the inside of the tubercle:
The other one made offsets at the border the the grafting stock:
Regrafted offset on Ferocactus glaucescens: