Donald Trump's casino company won a victory in bankruptcy court Friday, when a judge said the company's financial adviser could serve as an expert witness.U.S. Bankruptcy Court Judge Judith Wizmur rejected a plea from Trump Hotels & Casino Resorts shareholders who had argued conflict-of-interest problems should bar a UBS Securities LLC executive from testifying at a Feb. 3 hearing.The shareholders' lawyers had contended that UBS isn't truly a "disinterested" party and therefore UBS executive director J. Soren Reynertson could not serve as an independent expert witness in the case.UBS owns some Trump bonds, was underwriter for others and stands to get business from the company when it emerges from bankruptcy.