No I don't think they have this. How would I make sure the NU has my HPME recommendation?
Northwestern reviews applications “need blind” for US citizens, US permanent residents and DACA/undocumented students.
But would this need-blind situation be negated if I wrote in my additional information my circumstance (and status?).
No, you are still in the international group so it won't matter if you say you are on DACA or waiting for a green card. Does your father have his green card yet? If not, you are probably 6 months out from that date to get yours, at the earliest.
Are DACA/undocumented students considered in the "domestic pool" of applicants? If not, are they considered in the "international pool" or a separate "undocumented pool"?
All applicants are considered in the same highly selective admission pool.