Your posts are confusing.
How can your family pay $15k per year if their AGI is only $40k per year???
What kind of FA are you expecting?
Merit awards will likely reduce whatever aid you’re expecting.
Merit is applied FIRST, and then FA is awarded. It sounds like you think you’ll be awarded FA, and then your family will have a net cost of $15k, and then you can apply merit aid to reduce that $15k to 10k. It doesnt’ work that way.