Actually, in this case, Vixen's main mistake was going in Running Silent, since it wasn't necessary at all, and alerted the IC to her "malicious" intentions all that much earlier - Slicer was unmolested all the way up until he failed to get a mark on the book while Vixen was hounded from the get go. Granted, since she failed her first mark on the SC host, she would also have had trouble the moment she entered there, so it might not have made a tremendous amount of difference. Her generally low dice pools were also a major issue (10 dice vs. slicers 15 when using HotF). Also, during Turn 5, Vixen was denied her action at 28.
In short, the TM was out of her league.