Doesn't make it more ethical, no?
I think we left ethics long ago. OP is morally grey wherever you turn.
And is helping parents to have kids a bad thing? It's possible if it's a huge sample data of DNA that he can mix and match (differences between Kuina and Tashigi) and create a new kid that's not completely a copy. In that, it'd be a godsend for sterile parents in that world.
Genetically created kids that are created for loving parents are better than organic kids genetically altered to be weapons for a hateful parent.