You should work with an attorney to review the denial to determine next best steps.

How can i prepare for my marriage based interview question?

You should work with an attorney to review the types of questions that will be asked and what to expect. Good luck.

What kind of proof of our relationship would be valid for the nvc?

This may be in the form of cohabitation, comingling of finances, and other evidences of intimacy from the marriage including travel and communication.

Can I just go marry my fiancé in Haiti after my form i129f fiancé got denied ?

Yes you may marry and then file for I 130 consular processing. However the reason for the denial of the petition should be reviewed before filing.

I have passed my interview

These waits are very common and nothing to be concerned about. Continue waiting up to 120 days until a decision is made.

It is best to consult with an attorney for review of your case and previous filings.

Who is the petitioner in form i-759?

You, as the spouse beneficiary of the CPR would be the petitioner in the I751.

How long does it usually take to get a second waiver approval?

It can take between 12-16 months for a waiver decision particularly given your circumstances.

What should I do ?

You should consult with an attorney for guidance as you will need to amend your petition to a waiver based on the joint filing requirement.

Question about my travel.

It is not advisable to travel to the country you claimed asylum from.