No, jaguars do not kill gorillas in the wild because there are no gorillas for the jaguar to kill in the places where it lives. Gorillas are only found in Central Africa including Rwanda, Uganda and the Democratic Republic Of The Congo and Cameroon. The Jaguar lives in Central and South America and Mexico, thousands of miles away. It is possible that there are, extremely rarely, some jaguars at the very southern border of America but I’m not sure that this is true but there are plans to build a reserve there for jaguars.
However, Jaguars do kill monkeys if and when they are available because the jaguar eats pretty well anything that presents itself. The jaguar is not choosy as to prey and eats about 85 different prey species depending upon their availability. But gorillas are not on the menu. It begs the question whether a jaguar could kill a gorilla. That has not been tested to the best of my knowledge. I suspect they would conveniently avoid each other. This is the classic behavior of animals who can harm each other; common sense really and all about survival. Jaguars kill animals that weigh a thousand pounds, or three to four times the cat’s body weight.