Maybe the $$ or assets, if they are significant, could be left in trust on stipulation that they either get out, or that no money be given to WTS? I feel for you, that must be a hard decision. Or you could set up the $$ so that they have a small (very small) maintenance amount given to them each month/quarter in the event of your death. Yes, it may enable them to pioneer or whatever, but you can arrange it so they can never make one of those generous "inheritance" donations to WTS. Incidentally, my parents received an inheritance some time ago. They donated a substantial sum to WTS, just because it was "right." So IMO, you are right in assuming they would give a large portion away. It is just what is done by good Dubs in situations such as this.
Looking at it from the other perspective, my own parents (strict, or should I say fanatical JWs) have substantial assets. Originally, inheritance was 50/50 with me being executor. When my husband and I decided that we were not going back to JWism, I reminded him that it could mean significant financial "loss," when it eventually becomes known how far down this road we have come. His comment was that our convictions are worth more than any amount of inheritance, and we are not suffering anyways.
I suspect your dear daughters would feel the same about their convictions (unfortunately.) The revising of the division of assets will probably mean little to them, unless they are having doubts about the "truth." If they ARE having doubts about their beliefs, knowing they are giving up their inheritance for convictions they may not hold could make them think twice. Otherwise, it will have relatively little impact.
I am so sorry you are still battling this with your daughters. You are wise to consider the practical aspects of your choices though. (((((Dansk))))) ((((((Physio))))))
Odrade