WWE officials were aware of Lana and Rusev's engagement before the news broke last week and used that info to turn it into a storyline. But, just because he knew about it, doesn't mean Vince McMahon was happy about it.
I mean, I would like to think that Vince was happy for the two of them on finding true love and all that. But the Wrestling Observer Newsletter has noted that McMahon was not happy about the engagement because it broke the "rules" about maintaining character and playing the roles at all times.
The Observer also noted that it appears that current storyline plans were changed and rushed ahead because of the engagement news hitting the headlines.