Factual error: In the last scene the ICE Train is leaving the station eastbound. It is not possible to enter these trains at the central station because all eastbound trains end in Berlin and have only one station left (Berlin Ostbahnhof). Every ICE leaving Berlin is going in the other (westbound) direction.
Factual error: Jurgen takes the cyanide out of a coffee tin. He mentions he has had it for years since his time in the Stasi. However, in fact potassium reacts with carbon dioxide to form a harmless compound over time: to prevent this it must be sealed in an airtight container, which a coffee tin most certainly is not.
Factual error: Liam Neeson is holding a Rolex Deepsea marked "EH to MH 7.18.06." The watch was released in 2008.
Answer: Because the killers need to make Liam Neeson's death look accidental. The police think Neeson is crazy, and is not telling the truth when he claims Liz is his wife. The police simply think that Neeson is mentally ill and so dismiss his stories and allegations as untrue. However, if Neeson is then found murdered, there is the possibility that the police think Neeson might have been telling the truth, investigate, and foil the villains' plot. Therefore, Neeson must be killed to stop him investigating - but he must he killed inauspiciously, so it looks like an accident, so as not to make the police suspicious. Thus the poison in hospital - hopefully it would be put down as a standard non suspicious hospital death. And the drugs in the car park at the end of the film are deliberately mentioned by Professor Rodney Cole as being essential in making Neeson's death look an accident. Cole says that Neeson will seem to have killed himself with heroin and so will not consider his death suspicious. So basically these elaborate ways of killing are in order to make Neeson's murder seem an accident and so not make the police investigate.
swordfish