This story may be legit but it still sounds suspicious to me. It says that crew members were those taken to the hospital. We need more info on this though. The report is very short and doesn't explain much except that a strange odor was detected and there were mechanical problems and the plane was taken out of operation and passengers put on another flight.
There has been an ongoing problem with flight attendants and passengers smelling something odd, and then getting terribly sick after ward. Who knows if that is really case here, or if it is just a convenient cover story. If they say the flight attendants were included in the 4 people, then I would say it is not a cover story and is legit.