I didn't see this race yet, and although I enjoy watching it I'm no expert on road cycling. However, ISTR that in every televised race there is a particular motorcycle that stays with the lead rider(s). If a racer thinks she's on the front and doesn't see that motorcycle around somewhere, shouldn't she reconsider her position?

Also the racers who had been on the breakaway and got caught knew she was still up there, but they might not have cared to tell anyone about it.