Tsubaki's whole character is based around honor and justice. She has a strong bond for her friends and loves Jin/Hakuman. Yet all of these characters are rebelling against the NOL and she can't put two and two together to think "Hey, maybe my boss is evil...the one I've never seen and just have a weak family honor to uphold." And decided that all of her trusted friends and allies are dicks and decides they need to die for great justice.
Magic spells or not from the Imperator that's just lazy writing to set Tsubaki to be a sub boss for the next game. Not to mention it has absolutely no lasting value after the plot is resolved, just needless fluff. BB has never had that stellar of a story with it's massive plot holes and anime cliches thick enough to stop a bullet it's no wonder I can make so many satiric stabs at it. But hey, fighting games had always had the bottom of the barrel writing anyways.