Other mistake: The main character somehow finds Richard Aiken in a corridor that is locked with the armour key. The key is at the other end of the mansion so how did he get into the corridor without breaking the door down?
Factual error: In the Gamecube version the last entry in George Trevor's diary is dated "November 31st" November only has 30 days.
Plot hole: Why does Jill need to find keys? If she is the "master of unlocking" then she should be able to pick the door locks no problem.
Other mistake: Examining a green herb in the GameCube version will bring up the phrase, "An herb that's grow wild in this region." The phrase should've said "An herb that grows wild in this region."
Other mistake: In the "Plant 42 Report", it says "It has been effected by the T-Virus differently.", yet it should say "affected".