I've got experience of this happening to someone and it would have been better if she'd gone through with it then told him quietly that night she thought it was a mistake and requested an annulment
Sorry about what happened to your BIL, but that is one experience. I would be equally/more gutted if someone told me ON MY WEDDING NIGHT that the entire ceremony was a sham and they wanted the marriage annulled. And surely all the guests and family would find out what happened pretty soonish?
Leaving aside the ethically troubling part of making vows that you do not mean or intend to keep.
My BIL had to go back and face every single one of those people again knowing they'd all been talking and speculating on the ins and outs of his private life and hearing rumours
I seriously don't think it's the scandal you make it out to be. Yes, it will be the source of gossip but so are affairs, divorces, splits, getting fired etc. I would be more worried about my relationship breaking down than people talking about it. Plus, they would definitely talk if you were dumped on your wedding night, hours after the ceremony.
Additionally, in the case of non-consummation, you cannot rely on your own refusal to consummate the marriage- only the other person's. Therefore, it would have to be the groom bringing the nullity petition (which involves the same paperwork as a divorce and a court fee). So, not only do you get dumped on your wedding night, hours after a ceremony that turned out to be a lie, you also have to be the one who deals with bringing a nullity petition to court. But oh wait, people might not be talking about you as much.