I live in the United States and last year my brother and I purchased a house on mortgage (Riba), in both of our names, based on the Fatwa from Dr. Yousef Al-Qardawi that it was a necessity (Duroora). My father paid most of the down payment; around 70,000 and my brothers and I added 5,000 each.
I now feel that this was the wrong decision and want to repent and rid myself of this horrible sin. If I leave the house and begin renting elsewhere, the house will still remain partly in my name. My father does not want to sell the house and neither does my brother. I cannot sell the house because I am not the sole owner and the bank will not allow me to transfer my share to my brother's because his income would not be enough to guarantee the loan.
Even if I can get my brother to agree to sell the house, can we sell the house to someone who will buy it with a mortgage (Riba)? Because the cost of the house is about 500,000 and almost everyone willing to buy a house will not have this money in cash.
I asked a local Imam about this and he said that even if I leave I will still continue to carry the sin because the house is still partly in my name. I have tried warning my father about the dangers of this sin before but he still does not consider buying a house in this way is forbidden.
Please tell me what I should do in this situation to rid myself of this sin.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Riba (usury/interest) is forbidden. So, purchasing a house through it is also forbidden, regardless of whether it is practiced in a Muslim country or in a non-Muslim country. So, the one who has committed it should hasten to repent, feel sorrow for that sin and ask the Forgiveness of Allah.

One is not obliged to sell that house; rather, repentance is sufficient since the Riba is demanded by the bank; especially in your case, you did so relying on a Fatwa of some scholars.

Your sin in this dealing is paying Riba to others without any dire necessity. Jaabir, may Allah be pleased with him, narrated that the Prophet said “Allah has cursed the one who consumes Riba (i.e. usury or interest), the one who gives it to others, the one who records it and the one who witnesses it (its transaction).” He added: “All of them are equal in sin.” [Muslim]

To conclude, you have only to repent and you are not obliged to sell the house at all.

Allah knows best.