Was he always deceptive even from the beginning? I think that is really the question. Otherwise I would agree with you.I don't think he ever thought it had been washed out to sea - that is something he told the Council to mislead them and make them complacent, while he himself was actually looking for it.
I think you left out the words "makes no sense" after "Radagast". But really, it makes little sense even ifBut I agree with Corey that if you go by that story, Gandalf's going to Isengard when he gets the message from Radagast. Personally I think Saruman must have started out honest and