Because there was a trustee-to-trustee transfer you would not indicate that it was an inherited. For the #1 1099-R the Box 1=2a is as you say, a distribution to cover the RMD for your father. If the Box 1 amount included the amount sent to her account, you would indicate that it was inherited to show the rollover. I agree with you that the question is not a perfect fit in this situation.
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