Hi Anish.
Firstly, its good of you to come forward and admit it.
I can tell you 9/10 people don't have the courage to publicly admit they did something wrong. The fact that you have come clean is a significant step towards redeeming yourself. Theres not much I can do apart from give you some advice. So here it is....
Regarding the hack you want to submit - is it the same one that PB found? If so there would be little point in submitting it now as its already "registered" in the PB database.
If its totally different hack then it would be worthwhile to submit it.
IMO, it would be best if you submitted it yourself. The procedure is fairly simply from what I see on the Evenbalance site. You can simply email the hack to PB for submission. The email address link is on this page
PunkBuster Online Countermeasures
Just scroll down to where it says "To report hacks/cheats" and copy paste the email address in your mail account and send it to them.
You can possibly even do it anonymously if you like.
Just create a new mail account on any free web mail service (yahoo, gmail, hotmail etc.) and submit the hack to the email address provided from this new account. I don't think this should be a problem.
As for BC2, I would say get another copy and join us again on the RCDC Server with a new soldier nick. From what I know of Robins (RCDC Admin), he seems like a fair guy. As long as you play clean and fair he won't have a problem with your playing on his server regardless of your past.
Then again I am only guessing as I don't know him personally. As you have taken the step of coming forward like this, I for one would not have a problem playing on the same server as you. Other players however may not be as forgiving.
As it is people on the RCDC server tend to shout "hax0r" at anyone who kills them more than a couple of times. If they know your past I am pretty sure some of them -WILL- make life particularly hard for you on the server.
My advice would be to keep your new nick private for a while.
Everyone makes mistakes. Its what makes us human. The key is to learn from them and not make them again.
Hope that helps....