I looked in the instructions for the 709. Qualified Disclaimers are covered there. The 9-month deadline is mentioned. But no remedy is covered if the deadline was missed. One paragraph states:
"The 9-month period for making the disclaimer is generally determined separately for each taxable transfer. For gifts, the period begins on the date the transfer is a completed transfer for gift tax purposes."
Seems that the instructions would have been an appropriate place to state what happens when the 9 month period is missed. I suppose, in absence of a remedy, it is inferred that the Qualified Disclaimer rule does not apply and therefore the the surrender of the inherited property is considered to be a gift.
??
