Google is an enormous company which operates flatter than you’d expect for an organization of its size. It’s entirely possible that someone from Google was involved in organizing this (i.e. booking the venue) without having buy-in from leadership. Once leadership became aware after being asked about it, they may have shut the whole thing down because they knew the optics would be bad.
She would have lost Michigan and Wisconsin by even larger margins if she went with Shapiro instead of Walz.