Question: After removing the safety protocols from Chucky, why did the employee kill himself?
Question: Just after Chucky kills Shane, why did he say that it was for Tupac? Since he wanted Andy to be happy, shouldn't he have said that it was for Andy?
Answer: I wouldn't read into it much more than just a joke: Chucky heard that joke earlier when the kids in the street were trying to make him do things for their cell phone cameras. So he just re-used it later as he often does in the movie.
It was a joke that some kid said when he had the Chucky doll.
Answer: Yeah the kid said that so Chuckie said it too.
Answer: Chucky's A.I. enabled him to learn from others and through experience. Chucky was repeating what the neighborhood boy told him to say ("This is for Tupac"), but Andy's reaction to Chucky stabbing the stuffed unicorn was obviously negative - Chucky would have learned that stabbing someone would not make Andy happy. Hence, Chucky was demonstrating what he learned from Andy's friend/acquaintance and said, "This is for Tupac" (not "This is for Andy").
Chucky might have also thought that some kids view "This is for Tupac" as funny and an appropriate thing to say, but Andy did not because he stopped him when he was stabbing the stuffed unicorn. Also, Chucky didn't know what "Tupac" was or meant. That is, Tupac would not have been recognized as a person's name, so he would not know that he could substitute another person's name, such as by saying "Andy" instead.
Answer: The employee's bosses overworked and abused him. He was depressed, had emotional issues, and probably felt his life was hopeless. Before committing suicide, he wanted retaliation against the company for making him so miserable, so he disabled the safety protocols on the "Buddi" doll's computer chip. Mostly, it's a convenient plot point to explain how Chucky came about.
raywest ★