Quote Originally Posted by Sucrose View Post
A.) The odds of her vouching for him are rather low.

B.) He stated that he was there on urgent business, in marked contrast to both his admitted behavior and his general demeanor until questioned.

C.) After Claudia learns more, she will find out that Vi doesn't even work for the catering company that she hired, and so will know that he had absolutely no basis for assuming that she would be at the party. Frankly, the idea that he knew to ask about any one of their names at all is rather surprising.
Edit:
D.) She has a witness.

E.) For spreading rumors, it doesn't matter whether he can deny it or not. She likely will tell any and all parents she speaks with to keep an eye out.
Why wouldn't she vouch for him? It was urgent to him. He thought that having the soda with him would make him seem more like he would belong there. He only knows a few Bount. If she wasn't there than he could have just played it off as having the wrong house.