Help: Simplified Needs test and how non-custodial parent should fill out FAFSA

Looking for help understanding how the FAFSA and the Simplified Needs Test work in our divorce situation!

I am the custodial parent and have our kids ~80% of the time. Due to my recent financial situation, our college-bound son has qualified for both Medicaid & Free/Reduced Lunch for the past two years. I have also qualified for EIC.

Without doing nitty-gritty calculations, it looks like Dad has contributed a larger portion of the child support in the past 12 months. So, my understanding is that he'll need to be the parent contributor on our son's FAFSA.

My questions:

1. When Dad fills out the Financials section and it asks about the student or anyone in the household receiving means-tested programs, he should still select Medicaid, Free/Reduced Lunch, correct? (Since it applies to our son.)

2. Can he also select EIC since I received it, and I am also our son's family member and in his household? Or, does the question only pertain to the student and dad's household?

3. I know the FAFSA and the asset questions work on skip logic. By selecting any one of the above and meeting the Simplified Needs test, will this trigger the application's skip logic when our son fills it out, bypassing our SON's asset questions? (Or does it just allow dad to skip the parent asset questions?) Basically, I'm looking for confirmation on whether our son will still have to report his personal assets, such as savings.

4. Lastly, how should Dad report household size on FAFSA? He is unmarried, living alone, and has no other dependents besides ours. However, as I noted, he doesn't technically live with our children...he sees them for visits about 20% of the year. Although he currently pays the majority of support for our son, a second minor child, and contributes nothing for/to our third child in college (whom he doesn't see anymore). Should he report 3 as his household size, counting himself?