Post-NOIR: approval reaffirmation, what's next?

[SarAyouBliss 38]

Hello, hope everyone's doing good in here,

On April 12, 2013, my wife submitted evidences to the USCIS. The USCIS reaffirmed the approval of our petition on May 24, 2013 to make an end to the NOIR nightmare but not an end to the visa process. The NVC yesterday informed my wife that everything looks good, very likely an interview is scheduled but it's confidential until the right time to be announced.

We submitted our co-sponsor's I-864 + tax returns along with the package of evidences against the NOIR to the USCIS because my wife's last 3 years tax returns are not the best, ( she worked full 2012 >>>above poverty level, half 2011>>>above poverty level, nothing >>2010) knowing that the CO at my last interview (Sept 2012) emphasized that my wife didn't meet the financial criteria which can cause denial without looking at red flags or other factors.

Am i still supposed to have a copy of our co-sponsor's I-864 at the day of interview (original or just a copy) ? Should my wife fill out another I-864 and provide her last 3 years tax returns to combine it with our co-sponsor's package to present it at my next interview?

Although our case was reaffirmed, i'm not totally celebrating but grateful, i heard from couple of people that the reaffirmation means CO can't deny it but that's not necessrily true. I'd like to read from people who overcame the NOIR, what follows the NOIR, some details if available.

Thank you Bzaf.