Who Poisoned Yushchenko? Part 2.

I already wrote a post about Yushchenko's mysterious poisoning. Now Telegraph (UK) published an article based on an interview with a senior doctor from the Vienna clinic where Yushchenko was treated. Dr Wicke claims that no trace of poisoning was found. Soon the doctor was ousted from the clinic and received death threats if he makes this information public.
Dr Wicke remains uncomfortable about the role played by the Rudolfinerhaus in the drama. "The first two times Mr Yushchenko was examined, there was no evidence of poisoning whatsoever," Dr Wicke, 64, said. Yet, to his dismay, persistent leaks from the clinic suggested that the politician had indeed been poisoned.
Dr Wicke told reporters that a "medically forged diagnosis" had been circulated by someone "not permanently employed in this clinic". This was taken to refer to Nikolai Korpan, a Ukrainian-born surgeon who had been treating the politician in Vienna.
Three days later, Dr Wicke received a written request from Dr Michael Zimpfer, the president of the clinic's supervisory board, to retract his remarks.
Dr Wicke marked the memo with the word "Acknowledged". It was after this that a man speaking accented English rang Dr Wicke and introduced himself as "a friend from the Ukraine". He said the man told him to "take care. Your life is in danger". Dr Wicke and his family were then put under 24-hour police guard.
So, who really poisoned Yushchenko and was he poisoned at all?