About a year ago I was transplanting some of my ventricosas into deeper pots. One of them had a small basal shoot that was going to be buried several inches so I decided to cut it off and on a whim tried to root it.
This was the cutting then
and this is the cutting today
The point is, don't give up on a cutting without at least trying to see if it will take. You never know, these crazy plants fool the best of us.