What a CC will accept varies from bank to bank. Some will settle for half.
Generally, if a debt for which you are personally liable is canceled or forgiven, other than as a gift or bequest, you must include the canceled amount in your income. If a financial entity cancels or forgives a debt you owe of $600 or more, you will receive a Form 1099-C. Unless you meet one of the exceptions or exclusions discussed later, the canceled debt shown on Form 1099-C, box 2, is ordinary income from the cancellation of debt and must be reported on the appropriate form shown above.
My own personal experience is that the IRS is a stickler about granting the exceptions. The most common one is insolvency, and in my experience you have to be bankrupt for that one to apply. YMMV.

