"She does not have the original contribution dates or amounts. Nor does she know the amount of earnings in the account. Any suggestions on how to proceed?"

She can't get this from the ex? Or the brokerage holding the account (copies of statements) with the ex's permission? Or, the IRS, since there are Form 5498. And there might be conversions carrying their own 5-year clocks.

Obviously, this info needs to be produced for her own tracking and reporting.