First off she wont know.
You failed right there. The success of an ongoing, persistent, indefinite attack can't rely on the victim's not finding out about it. That is a recipe for a failed attack, and boom Alice is uncensored. It's easy to discover these attacks. Everyone will know something is up when the chain keeps re-organizing every 2+ blocks. They will spot who is behind the 51% attack and identify it as such, with these new 2+ block forks suddenly coming out of nowhere and reorganizing the chain, and possibly causing other havoc, not just to Alice.
The rest of your post is based on this same fallacy, so isn't worth responding to.
RE: Dan Larimer Cannot Censor Accounts with 51% of Hashes