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Is the CC in good standing? If so, have it report a very small balance.
See if you can get the collection deleted by sending a GW letter to the CA reporting.
Have your CC report a very small balance. Just keep trying the GW. If it is paid there isn't much more to do. FInd higher ups in the company to send it to.
If you need the score boost for credit that wont involve a manual review of your CR, being added as an AU might do the trick.