You are missing the point, which is students can always apply for federal aid.
It does not matter if the family is PELL grant eligible or if the family is deemed to be full pay and the only thing the student is eligible for is an unsub loan. The student can always file the FAFSA.
You are making a blanket statement that students will not be eligible for subsequent aid moving forward. While this is true at a small number of schools, it is not a hard blanket rule.
Looks like OP’s son is at Emory, where if student is eligible for institutional aid, they would receive aid if they filed the necessary financial aid forms.