Can I avoid Fed/State income tax on an inherited IRA withdrawal made to pay estate tax that wasn't deducted from the inheritance at the time of estate settlement in 2012?

The withdrawal amount is included in the 2017 1099-R. The "rationale" for income tax avoidance is that the amount withdrawn from the inherited IRA would not have been part of the inheritance (and therefore not subject to income tax) had the estate tax had been properly deducted at the time of settlement.