I double-checked the latest IRS form 1116, and the only mention of withholding is "Taxes withheld at source" in Part II.
Yes, it could be the IRS verification process. If Intuit could establish whether that is the cause instead of TurboTax, maybe they could seek a correction or not, but we'd know that we can't file online yet -- and who knows whether the paper copies will be rejected by the same IRS software.
