$15k short—if OP throws some money in there, and borrows some using PLUS loan proceeds as loan to D, all documentation done for loan scenario, that could work.
Problem is that it’s a redo for sophomore year. With FAFSA asking for income two years prior to the school year for which financial aid is being requested, if the daughter graduated in 4 years, one can start pulling funds out of the 529 to pay tuition, and to repay the loanS up to $20k. But be aware, things happen, and an extra year often is needed, not just because a student needs more credits or courses but things like this pandemic can happen, things that involve taking a gap year. I’d wait till second semester junior year before breaking into the 529
Some valid points raised about EFC changing when there are no longer more than one student in college. Also, OP says in first post that there isn’t enough in the 529 to pay that first year balance. That means no $80k sitting there to repay.
OP should run some numbers to see what the 4 year cost is likely to be, keeping in mind that there may just be one in college which will likely end PELL eligibility.
There is an radiation allergy $4k in studebt Direct loans in another year is needed for college, this the $31k number.
Good luck in coming up with the magic formulas for your D to maximize financial aid possibilities