Do I Have To Dissolve Adoption To Be Qualified For Fasfa?

For background I am living in Iowa but lived in Missouri for most of my life. I was sexually abused by my biological father when I was younger. I was in foster care from age 10-11 ish. My biological father was not charged. I was then released to my mother legally. From age 13, I lived with my mom’s husbands grandparents (my step dad’s parents). At 15, I was officially adopted into the family by those grandparents. There was a plea deal that if my biological father gave up parental rights, we (my grandparents) would not press sexual abuse charges. I moved out at 19 because of emotional manipulation/abuse from my grandmother in that household.

My problem is that I am now 21 and live in Iowa. I am wanting to finally attend college through fasfa/grants. My grandfather (my adoptive father now) refuses to provide tax documents so that I can qualify for fasfa. According to fasfa, I am NOT independent. I do not have kids. I am not married. I was not in foster care at 13. I do not legally qualify to be an independent adult according to them. I do not have the money to pay out of pocket for college. If I do not go to college, that basically sets me up for failure because I literally NEED an education. Again, my adoptive father refuses to provide tax documents so that directly puts me in a situation where I have to pay out of pocket.

My question is, should I attempt to dissolve the adoption? I don’t really care about getting the last name of my abuser back. It’s just a name. I just need to be able to have my parents tax documents to provide. I live with my real mother and her husband, who can provide documents but they are not legally my parents. My biological father is in prison for unrelated charges, who cannot provide documents and I absolutely refuse to contact him (I don’t even know if I can)

Do I attempt to dissolve the adoption to try to get covered by fasfa? Is there any other option besides that? What do I do? TIA

Location: IOWA