Every JW deserves to know TTATT. But special care needs to be exercised when sharing it with some - those who the OP says do not qualify. They do qualify but they need special professional counseling to change their whole outlook in a gradual manner, before sharing TTATT with them.
So I think the points made by the OP are valid, not as it pertains to who qualifies to learn TTATT, period. But specifically as it pertains to who is in a position to learn TTATT raw from layman ex-JW.
it might be a good idea to think of what type of questions to ask a JW to determine if they're ready for TTATT from a layman ex-JW. Some questions might be:
If hard, indisputable evidence came to light proving that JWs really do not have the truth, would you want to know?
If you discovered that this is not the truth, where do you see your life headed - what would you do with your life?