Charged off bank debit account, sold debt to third party. Who should I negotiate with?

I have a credit account that was charged off, but the creditor has sold the debt to a third party. and they say they can't help me. Should I still try to negotiate with the original creditor or deal with the third party? Will the third party be able to update my credit reports with "paid as agreed"? thanks,
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Can't help you do what?

A creditor can only update it's records, not another party.
Debt validation helps with second and third parties

I re-opened a charged off bp oil credit card.
After sending them 340 dollars to pay the debt and fees, I also sent bp oil 300 (after talking to them about what I wanted to do) to reopen the past bad account and that I wanted to join the world of reasonable people who have good credit.
After 12 months I asked them to remove the old bad marks.
BP Oil removed everything that was over 2 years old (since revolving credit, credit cards, usually only report the last 24 months and I asked them, begged them) and paid more than I charged each month for 12 months straight.
I have a BP oil card in my pocket right now saying member since 1992, the year they charged me off.
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I want to pay off the bad debt and clean up my credit report. It's a debit card on a checking account I closed in 2000, but they say the checking account is still open and I owe $50 on the checking account. They don't have any records, but they suspect that the $50 charge is what ran up the debit card. Thankfully the debit card had a max of $500. That is what they charged off. But for some reason I have three accounts on my credit report from them that say "charged off". All three with the $500 value. 2 of the accounts are related. The third they can't find any record of. of the 2 accounts that are related, one of them was sold to a 3rd party. This 3rd party has sent collections people to find me.On the account that was sold, the bank says they can't help me and I need to talk to the 3rd party. After I do that I can talk to the banks credit bureau to get the other two accounts cleaned up.
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Dispute the third one they can't find.
Negotiate with the collections or third party to make sure if you pay, the account will not be placed on your credit report or, that they will take it off if I pay in full now.
Even if they have already put this on your report and will not take it off completely if you pay, still pay them so it will show paid off and drop your debt to high credit ratio for that one account.
oh.
and you might as well just forget about, the other one, they said they can't help you with.
in 24 months or less it will not matter much anyway