Please don’t think this is an unusual situation. About 1/2 the states require all child support to be paid through the court registry, even if everyone agrees it can be paid directly, and there is a good reason - most people who are divorced don’t communicate all that well. The court takes the option of paying, or when to pay, or how much to pay, out of it. Minnesota has had required payment through a court registry, directly from the employer who withholds the court ordered amount, to the registry, to the custodial parent, for 30+ years. No opting out.
Also, do not think that just because child support ends at age 18 your father won’t be expected to contribute to college. CSS colleges will be expecting to see his information and will decide how much he should be expected to contribute.
Anyway, there are tons of schools that are FAFSA only. Most public schools are and some give good merit aid - Alabama, Ole Miss, Miss State. If you are National Merit, all the Florida schools.
Your EFC after filing FAFSA may show you get a Pell grant because there are 2 in college (I would guess it will be close if there is only 1 in college on a $70k salary).