If RC had passed his polygraph, what possible reason could LE have to not publicly state that he had passed it? I can assure you that if I had taken a test of this nature and KNEW I had answered the questions truthfully, LE's going to have to release the results and clear my name, or explain to a judge why not after I sued the hello out of them.
If they're going to tell the media that they had given me the test, they're going to have to tell the media when I passed it. There's no way that I'm going to walk around in my community with a cloud of suspicion hanging over my head if I was innocent.
Since LE has been their usual stone wall on the matter and Mr "I was at werk" hasn't demanded his name be cleared by the results being released, there's only one reasonable conclusion to draw.
He doesn't want a failed test to be released.