The size of the joint that Richard is smoking on the loading dock changes from when Richard is talking to his wife to when Doug catches him.
Richard Welhner is from Québec, and his car has Québec plates, but vehicles from this province only have license plates on the rear of the vehicle, not on the front.
When Doug reads the first complaint card, first shot is a visual of the card while he's reading the first line, which matches what is heard on audio, but when the visual cuts to a shot of his face while continuing reading, the line heard on the audio is not the one following the first as seen on the card in the previous shot.
Only a self-defeatist would hide a junior Olympics championship they had won if they were up for a promotion., as Doug does.