So…if I’m understanding correctly, you are going to force your stepdaughter to accept merit money so you can spend more money on 2 of your own kids who, based on your posts, are unlikely to get merit money
AND
You want her dad to take some of the money from the sale of a premarital asset–which you previously agreed would go to his daughter–and spend it on your kids.
AND
Your proffered reason for doing this is to “make things fair.”
Personally, i think that plan is a LONG way from “fair.”