@bgbg4us Thank you for the great news and update! Bless your parents and your family for opening your hearts to them. Truly, their story is the American Dream!
As for college costs, ND is full need met, so if their EFC is low then ND will fill in the rest (I know from firsthand experience). If there’s still a gap financially, they should contact ND ASAP to see if their forms are correct, or if there is additional information that might change the FA offer. I’d first try the Financial Aid office, then maybe his designated regional admissions counselor if that doesn’t work. https://admissions.nd.edu/connect/find-your-counselor/
Do this ASAP as April 30 is right around the corner. Best wishes!