Analysis of information sources in references of the Wikipedia article "Resident Evil 2 (2019 video game)" in English language version.
A day passed by, and September 29th marked a new day, as the chronological events of Resident Evil 2's gameplay begin at this point.
Leon eventually met Ada Wong in the police station, who stated she was there on an assignment by the FBI to incriminate those responsible for the outbreak and G Virus, and that she was looking for a sample to use as evidence against them.
It turns out that Chief Irons was in the pockets of Umbrella all along, and helped cover up the mansion outbreak that transpired in the first game months prior in the timeline, which explains why no more investigations into the matter had followed.
When Claire finally found Sherry deeper in the sewers, she discovered that William Birkin found her already and infected her with the G Virus. As is discovered, William Birkin was hunting for his daughter because he wanted to reproduce. He was convinced that her body would not reject the G Virus, given their DNA is related.
In September 1998, Raccoon City becomes overrun with zombies after the T-virus contaminates its water supply, infecting much of its population.
In the sewers Leon and Ada run into William's wife Annette, who is... not a big fan of law enforcement, to say the least. Leon and Ada chase her to a secret Umbrella underground facility called NEST in pursuit of the G-Virus.
Annette tells Leon that Ada is actually a mercenary who's looking to sell the G-Virus to the highest bidder. Ada demands the G-Virus, But before Leon can hand it over, Annette manages to shoot Ada. She falls to her death, dropping the G-Virus sample.
The facility is set to self-destruct, and Claire and Sherry board a train to escape with Leon. With NEST destroyed, the crew finally manage to escape the nightmare and on the outskirts of Racoon City vow to continue their fight against Umbrella.
