Disputing requires that you assert some inaccuracy in their reporting, and is a frivolous dispute if no assertion of inaccuracy is provided.
GWs of charge-offs are particulary difficult, as the creditor made the prior determination that your debt was at such a stage of delinquency that they could write off that asset as an uncollectible bad debt. So you enter into a GW request with that perception having been stated.
You are also asking that they delete based on payment of the debt, which is directly contrary to written policy of the CRAs.
In my opinion, plain vanilla GW requests are most likely going to meet with plain vanilla denial.
What most do in such a situation is to attempt to locate the name of a management official in their company who has the authority to grant exceptions to their normal policy.