She can't make that argument if she wasn't Trump's attorney (she wasn't) and her charges have nothing to do with the validity of the charges against Trump and his campaign team.
If the charges against Trump and Powell are based on the same statute or legal theory, Powell could get her conviction overturned if Trump is vindicated. In such a manner Conrad Black went from federal prison to free man. He had lost at trial and all appeals, but when the legal theory applying the fraud statute used against Black was overturned by the US Supreme Court in an unrelated case, Black’s conviction was quickly vacated as well.