Mary Martin convinced fellow Canadian Leonard Cohen to not go to Nashville and instead stay in NYC. She then introduced his songs to Judy Collins who then recorded several and Cohen then went on to sign with John Hammond at Columbia records. Much later in his career Mr. Cohen was defrauded by his long term business manager, someone not named Mary Martin.
Why some people want to denigrate an influential, loved and respected individual on their death is beyond my comprehension. It says something about them, not about Mary Martin.