Josh, one other thing I did was allow the females to hold longer, up to 19 or 20 days, and that seemed to help in my early experiences and although the yields were only about 50% it was better than losing the entire brood each time. One word of caution if you wait as long as I did to pull the fry: the females will spit in the tank when they are ready so if you miss the full-term day the fry will be released early in the morning and eaten by adults in the tank pretty quickly.
I've also tried isolating females in smaller tanks to release naturally but in both cases of trying that the females stressed so much they died overnight and the fry remained in their mouths but were dead each time. I had them in 20H tanks when isolating them. The species is not an easy one. Otherwise, you'd see them available more often and from more sources.