This is the first time that it has popped up on the radar probably since 1967. The OBots didn't know about it until now or very very recently.
The 2011 CRS White Paper does not discuss a fact pattern where only one parent of a foreign-born presidential candidate was a citizen at the time of the candidate's birth.
Without even looking at it - it is highly likely ...99.9998% certainty that it is bunk.
I searched www.opencrs.com and found no trace of the November 1967 CRS opinion.