Other mistake: When Fievel And Tony reunite on the streets of New York, Tony gets a piece of cheese off of a mouse trap. Watch that piece of cheese, cause Tony throws it up in the air, and you never see it come back down. (00:33:25)
Other mistake: Fievel and his family are Russian and live in Russia at the beginning of the movie, but only Fievel's parents have Russian accents, whereas Fievel and his sister have American accents. This is especially odd since they end up immigrating to America.
Answer: Warren T. grabbed Tiger and told him he was fired.Tiger did eventually leave some time after that though.