His judge-alone retrial began in front of Supreme Court Justice John McKechnie on Monday.
At the beginning of the hearing, Schmidt said he would plead guilty to manslaughter but that offer was rejected by prosecutors who are pushing on with a murder case.
Mr Sylva told police he had watched Schmidt argue with another man before he approached Mr Marshall.
In his statement to police he said he followed Schmidt from the lobby into the bar because he wanted to calm him down and ask him to leave.
Yesterday defence lawyer Colin Lovitt accused Mr Sylva of lying to "big note" himself, the West Australian reported.
Mr Sylva admitted that in hindsight, some of the statements were not correct, but insisted he had a good view of the incident. He said that while he now realised he did not follow Schmidt into the bar, he saw everything unfold from the lobby.
Another man who was in the nightclub, Dean Banning, 24, told the court he saw Schmidt push Mr Marshall with both hands. Schmidt then punched another man before leaving the pub, he said.
Prosecutor Bruno Fiannaca told the court on Monday that Schmidt, in a "fit of rage"had pushed Mr Marshall, 29, so hard he crashed through the window and fell five metres.
CCTV footage from inside the hotel before the incident and of Mr Marshall landing on the footpath outside was played to the court.
Schmidt could be seen walking out of the hotel and glancing towards where Mr Marshall lay before disappearing.
Mr Fiannaca said text messages sent by Schmidt to a friend and his girlfriend would show he was not shocked by the incident, the West Australian reported.
Schmidt's retrial was ordered after the Appeal Court ruled there had been a miscarriage of justice because the trial judge did not adequately direct the jury on an essential element of the case against Schmidt.
Mr Marshall is the cousin of Feilding farmer Scott Guy, who was shot dead at the end of his driveway in July 2010.
Mr Marshall's parents Alan and Wendy, from Hawkes Bay, are at Schmidt's retrial.
