As her rivals thundered down the sinuous Yanqing sliding track on Tuesday preparing for the chance of glory later this week, Katie Tannenbaum was stuck in he COVID-19 isolation room for the seventh day, watching her Olympic dream slide away. The sole representative of the U.S. Virgin Islands is desperate to get out. Tannenbaum tested positive in one of the Olympic villages, though she has now had several days of what should be negative tests, she said. But the standards for what would allow her to get out keep changing. “The IOC (International Olympic Committee) won’t even provide a clear definition of what constitutes a negative test result,” she said in a message sent from her isolation room. “It’s really hard mentally. This isn’t the Olympic experience I imagined,” added the 36-year-old. “They don’t provide any excuses, someone will just say the other person you got information from was wrong.” …