You do not need to amend your state tax return for that. The requirement to receive a TABOR Refund is to file a tax return by the due date - 04/15/24 (including...
You need to file Form 1040-NR to claim the refund. TurboTax does not support the form but you can use the partner site to file it. Please read more about it her...
You summarized the plan of action well. Have you completed any of those items?
There is nothing to file with the IRS except for indicating that the Schedule K-...