The only real way to account for a foreign income tax refund related to prior year returns would be to go back and amend these prior returns.
Go back to your prior years and recalculate your foreign tax credit with the amounts reduced related to these foreign tax refund payments. If the only change is a change in the foreign tax credit carry forward amount, then do not file any amended tax returns but recalculation the foreign tax credit carryovers for the current tax year.
If your tax liability changes due to this reducing in available foreign tax credits in those years, then you will need to file amended tax returns and the reason for amending would be "refund of foreign taxes claimed as foreign tax credits".
Here is a link on How
to Amend a Return You Already Filed
