I think when it comes to game play about HOH, VETO etc, those that have unaired are spoilers, but being that the Victor/Nicole news is on Social Media/News sites, whether it's airing or not, is not a spoiler to game play and not to cause issue but I disagree about it being a spoiler.
The proof is is right here that it's all over the internet:
'Big Brother' Alums Nicole Franzel and Victor Arroyo Get Engaged During Visit Back to the House
Big Brother 20: Nicole And Victor Get Engaged
‘Big Brother’ Alums Victor Arroyo and Nicole Franzel Are Engaged
'Big Brother' Alums Victor Arroyo and Nicole Franzel Get Engaged
‘Big Brother’ Couple Nicole Franzel and Victor Arroyo Are Getting Married
I don't mean to disrespect anyone's opinion of course but when it's all over the internet, even though there will likely be a segment on the next BB episode, it's not spoiling anything to the current game play.
I think it's a fine line and if game play results were revealed because of their announcement it would be another issue, but nothing about game play is revealed.