A jury award of nearly $1 million to former WSVN health reporter Marilyn Mitzel for age discrimination at the hands of station management was wiped out Wednesday by an appellate court. The Third District Court of Appeal reversed the 2010 jury finding that Sunbeam Television Corp., WSVN’s owner, fired Mitzel three years earlier because she was too old for television, and ordered a Miami-Dade court to reconsider the case.