Proof of Parents US Citizenship

For my SF86 it was held back because I don't have any documents passport or naturalization certificates for both of my parents since they were born in Mexico. I've attempted to contact them but they weren't cooperating and I submitted a documents release through USCIS FOIA.

Does anyone have any experience with this and is there anyway to bypass it? This is the only thing holding me back at the moment.

I've completed everything else as far as enlistment goes ASVAB, MEPs, etc.